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Perspectives on the Utilization of Aquaculture Coproduct in Europe and Asia: Prospects for Value Addition and Improved Resource Efficiency


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Aquaculture has often been criticized for its environmental impacts, especially efficiencies concerning global fisheries resources for use in aquafeeds among others. However, little attention has been paid to the contribution of coproducts from aquaculture, which can vary between 40% and 70% of the production. These have often been underutilized and could be redirected to maximize the efficient use of resource inputs including reducing the burden on fisheries resources. In this review, we identify strategies to enhance the overall value of the harvested yield including noneffluent processing coproducts for three of the most important global aquaculture species, and discuss the current and prospective utilization of these resources for value addition and environmental impact reduction. The review concludes that in Europe coproducts are often underutilized because of logistical reasons such as the disconnected nature of the value chain, and perceived legislative barriers. However, in Asia, most coproducts are used, often innovatively but not to their full economic potential and sometimes with possible human health and biosecurity risks. These include possible spread of diseased material and low traceability in some circumstances. Full economic and environmental appraisal is long overdue for the current and potential strategies available for coproduct utilization.
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Critical Reviews in Food Science and Nutrition
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Perspectives on the Utilization of Aquaculture
Coproduct in Europe and Asia: Prospects for Value
Addition and Improved Resource Efficiency
Richard Newton a , Trevor Telfer b & Dave Little b
a Institute of Aquaculture, University of Stirling, Stirling, FK9 4LA, UK , Stirling , FK9 4LA ,
United Kingdom
b University of Stirling, Institute of Aquaculture , Stirling , United Kingdom
Accepted author version posted online: 19 Oct 2012.Published online: 15 Nov 2013.
To cite this article: Richard Newton , Trevor Telfer & Dave Little (2014) Perspectives on the Utilization of Aquaculture
Coproduct in Europe and Asia: Prospects for Value Addition and Improved Resource Efficiency, Critical Reviews in Food Science
and Nutrition, 54:4, 495-510, DOI: 10.1080/10408398.2011.588349
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DOI: 10.1080/10408398.2011.588349
Perspectives on the Utilization
of Aquaculture Coproduct in Europe
and Asia: Prospects for Value
Addition and Improved Resource
1Institute of Aquaculture, University of Stirling, Stirling, FK9 4LA, UK, Stirling, FK9 4LA, United Kingdom
2University of Stirling, Institute of Aquaculture, Stirling, United Kingdom
Aquaculture has often been criticized for its environmental impacts, especially efficiencies concerning global fisheries
resources for use in aquafeeds among others. However, little attention has been paid to the contribution of coproducts
from aquaculture, which can vary between 40% and 70% of the production. These have often been underutilized and could
be redirected to maximize the efficient use of resource inputs including reducing the burden on fisheries resources. In this
review, we identify strategies to enhance the overall value of the harvested yield including noneffluent processing coproducts
for three of the most important global aquaculture species, and discuss the current and prospective utilization of these
resources for value addition and environmental impact reduction. The review concludes that in Europe coproducts are often
underutilized because of logistical reasons such as the disconnected nature of the value chain, and perceived legislative
barriers. However, in Asia, most coproducts are used, often innovatively but not to their full economic potential and sometimes
with possible human health and biosecurity risks. These include possible spread of diseased material and low traceability
in some circumstances. Full economic and environmental appraisal is long overdue for the current and potential strategies
available for coproduct utilization.
Keywords Processing, fishmeal, omega-3 oils, regulation, halal, kosher
Fish production from capture fisheries and aquaculture
has received criticism for inefficiency of resources and envi-
ronmental damage. Whereas capture fishery production has
remained fairly static at around 90 million tons, aquaculture
production has steadily increased from 26.7 million tons in
1996 (FAO, 2002a) to 51.7 million tons in 2006 (FAO, 2009a).
Global aquaculture production is dominated by China at
62% by volume in 2009, largely for domestic markets (FAO,
2010). However, the rest of the world has seen rapid expansion,
representing significant trade and income. Globally, aquaculture
continues to be the fastest food growth industry, expanding at
a rate roughly four times that of terrestrial livestock species
combined (FAO, 2009a).
Address Correspondence to Mr Richard Newton, MSc, Institute of Aquacul-
ture, University of Stirling, Stirling, FK9 4LA, UK, Stirling, FK9 4LA, United
Kingdom. E-mail:
In addition to food capture fisheries, in excess of 30 million
tons of fish are caught each year for nonfood purposes, mainly
for the manufacture of fishmeal and oil for use as feed and
feed supplements in aquaculture, pig, and poultry production
(Figure 1). Aquaculture especially has often been criticized for
inefficient use of fishmeal and oil, which could perhaps be used
for direct human consumption (De Silva and Turchini, 2008)
and for putting pressure on supplies which can threaten ecosys-
tems (Alder et al., 2008). However, little attention has been
paid to the potential for aquaculture to produce fishmeal and oil
to feed other livestock through processing of coproducts. For
the purposes of this review, coproducts are defined as parts of
the animal, other than the fillet, which may have some value
but are often under-utilized. Byproducts are defined as those
parts which cannot readily be used to add value and must be
disposed of. Where mortalities may be considered as byproduct
or coproduct, they will be referred to separately. In 2008, the es-
timated quantity of fish used in fishmeal and oil production was
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Figure 1 Trend in price and distribution of global fishmeal production for aquaculture and other use (detail where available). Source: (De Silva 2008; FAO
2002a, 2010; International Monetary Fund 2010; Seafish 2009a, 2010; Tacon and Metian 2008).
20.8 million tons, although this is significantly lower than the
estimated 30 million tons used in 1994 (FAO, 2009a). Although
the quantity of fishmeal used in aquaculture has remained fairly
constant for about 10 years at around 3 million tons, the total
supply has varied greatly, due to El Ni˜
no events for example.
This has resulted in highly fluctuating prices for both fishmeal
and oil and increasing pressure on the aquaculture industry, par-
ticularly that of carnivorous fish such as salmon, which still
consume large quantities of fishmeal.
The reliance of aquaculture on fish oil is even greater than
fishmeal, and is estimated to utilize between 80% and 90% of
global supplies annually, compared to the 1970s when most was
directed toward hydrogenation plants to be converted to trans-
fats, used in margarines for example (Bimbo, 2007). The recent
promotion of omega-3 fatty acids as health promoters has seen
an upsurge in the demand for encapsulated fish oil, growing
at over 4% per annum between 2003 and 2007 in the United
States (Snyder, 2010), putting further pressures on prices and
supplies. As many of the capture fisheries used for fishmeal and
oil production are fully exploited (FAO, 2002b; Fishmeal Infor-
mation Network, 2008), it is becoming increasingly important
to maximize the efficiency of resource use from aquaculture and
fishery products. In addition, with increasing production costs
and competition, profit margins have been squeezed for many
producers (Borch, 1999; Lam et al., 2009). It is therefore be-
coming more important to add value to the product wherever
possible throughout the value chain.
While there has been some research to investigate the poten-
tial for coproducts, lack of knowledge transfer, logistical bar-
riers, and the strict European Union (EU) Animal By-Product
Regulations (European Commission, 2002, 2003) have proven
prohibitive to European products and imports to the Euro-
pean Economic Area (EEA, the 27 EU countries plus Nor-
way, Iceland, and Liechtenstein). Many technologies are avail-
able that enable value to be added through coproducts, and
these are often used innovatively in Asia. However, there are
areas where efficiency can be massively improved in Europe
and Asia by employing such technologies and a full study
of methodologies is long overdue. In some cases, scaling to
commercial levels still remains a challenge in respects to pu-
rification, efficiency, documentation, and verification of health
claims, commercial licensing, and marketability. (Raghavan and
Kristinsson, 2009; Thorkelsson and Kristinsson, 2009). There
has been little progress into how to integrate the technologies
and ideas for the aquaculture sector and the organizational struc-
ture to facilitate their uptake in terms of cost benefit, envi-
ronmental impact, and future projections. However, fish prod-
ucts may have particular advantages over porcine and bovine
products for religious reasons, particularly in Asia, and there-
fore aquaculture products hold significant opportunity for value
This review discusses the current and prospective technolo-
gies available, previous studies on coproduct, comparisons with
current practices, and how future research and development
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Tab l e 1 Fillet yield, expected mortality, and proximate analysis of whole carcass and entire coproduct postfilleting, for farmed Atlantic salmon, striped catfish,
and penaeid shrimp
Fillet Omega-3
Species yield % Mortality % Water % Protein % Lipid % Ash % FA,% total
Whole animal
Atlantic salmon 6215265.9318.9313.732.6339.34
Striped catfish 35530676.8712.875.674.07
Penaeid shrimp 50855974.910 18.010 1.210 3.410 22.911
Atlantic salmon 62.1316.9319.134.7343.612
Striped catfish 73.613 11.813 7.913 5.613
Penaeid shrimp 69.314 18.914 1.214 5.814 19.114
Whole animal figures for striped catfish were taken from fingerlings of average weight 7.6 g. Atlantic salmon and penaeid shrimp figures from market size animals
except whole shrimp omega-3 content is for Indian white shrimp, Fenneropenaeus indicus at average weight 17.6 g, all others are for the black tiger shrimp,
Penaeus monodon. Coproduct figures are extrapolated from whole fish quantities, fillet yields and quantities.
Source: 1. Ram´
ırez, 2007; 2. SEPA, 2004; 3. Einen and Roem, 1997; 4. Stubhaug et al., 2007; 5. Le Nguyen 2007; 6. Lam et al., 2009; 7. Hung et al., 2010; 8.
Benjakul et al., 2009; 9. Briggs et al., 2005; 10. Focken et al., 1998; 11. Ouraji et al., 2009; 12. Higgs et al., 2006; 13. Polak-Juszczak, 2007; 14. Sriket et al., 2007
should be directed in order to maximize efficiency and sustain-
ability in a number of contexts.
European Economic Area
Aquaculture in the EEA is dominated by salmonid produc-
tion, particularly Atlantic salmon, the majority of which is
grown in Norway. Here, the combined production of salmonids
was in excess of 800,000 tons in 2008 (Norwegian Directorate of
Fisheries, 2009) and more than the EU27 marine finfish aquacul-
ture production combined (Zampogna, 2009). Estimated fillet
yields from farmed salmonids are about 62%, with 9%, 18%,
9%, and 2% wet weight, making up the viscera, head, backbone,
and skin, respectively (Table 1) (Ram´
ırez, 2007). The most sig-
nificant coproduct streams are viscera at the point of slaughter
and then the heads, bones, and often the skin after transportation
to the processing plants. In some circumstances, the slaughter
and processing may be combined.
Norway exports more than half of its product (Whole Fish
Equivalents, WFE) to the EU as whole/eviscerated fish, mostly
for further processing (Global Agriculture Information Net-
work, 2007) and further exportation within the EU (Figure 2).
Despite this, according to RUBIN (2009) there was at least
60,000 tons of salmon coproduct available in Norway in 2008.
Recently, much of the processing of eviscerated Norwegian
salmon has moved from Denmark and Germany to eastern Eu-
ropean countries, such as Poland (Norwegian Seafood Export
Council, 2009). The United Kingdom, specifically Scotland, is
the second largest producer of cultured salmonids within the
EEA, at around 150,000 tons, an estimated 38% (WFE) of
which is exported (SSPO, 2009). The remainder of fish cul-
tured in Scotland are processed in the United Kingdom along
with an additional 40,000 tons WFE which are imported from
Norway (in 2008) (Norwegian Directorate of Fisheries, 2009).
The UK salmon processing industry has consolidated over
the last 10 years with the number of plants reduced from 145
to 48 but with a slight increase in the number of employees
between 2001 and 2008 (Seafish, 2009a). Consolidation has al-
lowed some processors to produce a range of commodities, such
as Pinneys of Scotland, who produce smoked fillet, mousses,
and ready meals. This trend has the potential for more efficient
use of coproduct. Despite opportunities for value addition from
within the United Kingdom, over 25,000 tons of the estimated
52,400 tons of processing coproduct from UK farmed fish in
2003 was exported (SEPA, 2004).
Aquaculture coproducts have advantages that they are of-
ten more uniform and fresher than those obtained from capture
fishery processing (ˇ
e et al., 2009). Frequently changing
socio-economic conditions and consumer attitudes have led to
continual restructuring and a fractured nature of the aquacul-
ture processing industry in the EU, resulting in excessive trans-
portation, diffuse availability and a potential loss in quality of
coproduct and potential revenue. Studies have shown that co-
products not only contain significant amounts of omega-3 fatty
acids (FAs) (see Table 1 for proximate analysis and references)
but substances, such as collagen and peptides (see below) which
have potential to yield products of high value.
Currently, companies in Scotland, Norway and Denmark ex-
tract the oils from farmed salmon processing coproducts, and
produce protein concentrates and oils intended for use in pig
or poultry feeds (Thistle Environmental Partnership, 2008). For
example, Hordafor, Denmark, produces around 30,000 tons of
protein concentrate from around 100,000 tons of aquaculture
coproducts per year and also treats mortality waste for biogas
production (see below) (Leivsd´
ottir, 2010 pers. comm.).
Markets for some salmon processing products such as heads
are well established in Vietnam and they can be seen for sale
commonly in major supermarkets as well as in local markets for
around 30,000 VND (about US$1.45) per kilogramme. There
is at least one company in the United Kingdom (Ideal Foods
Ltd.) which exports aquaculture and fishery coproducts to Asia
and other locations. Some Asian countries also import other
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Figure 2 Distribution of farmed eviscerated Atlantic salmon produced in Norway and the UK for further processing during 2008. Source (Norwegian Directorate
of Fisheries 2009; SSPO 2010 unpublished data).
livestock coproducts such as chicken feet from the West. The
import of coproducts demonstrates different values attached to
various animal products by different countries. More research
is required to establish the demand for coproducts in various lo-
cations and weighed against other value addition options closer
to the processing areas.
Although mortalities from production do not enter the human
food chain, they have the potential to alleviate the burden on fish
meal and oil supplies that are suitable for human food produc-
tion, by directing them to feeds for pets and other nonlivestock
feeds. According to De Silva and Turchini (2008), around 13.5%
of the global forage fish catch suitable for fishmeal inputs into
human food production was directed to pets and animals farmed
for their fur in 2002. Chronic fish mortalities (e.g., sea lice in-
fection) amount to between 5% and 10% of the total salmonid
production, for Scotland and Norway (SEPA, 2004; Statistics
Norway, 2009). On occasion acute local or widespread catas-
trophic mortality events occur through disease, algal blooms
(Treasurer et al., 2003), jellyfish (SEPA, 2004; Fisheries Re-
search Services, 2010) or extreme weather (SEPA, 2004). A
weather or disease event may result in the loss or culling of
an entire farm stock of several hundred tons. The slow accu-
mulation of chronic mortalities means they are of little value
but schemes such as "The Fallen Stock Scheme" may allow
for more efficient collection, lower costs, and better utilization
(Bansback, 2006).
The rapid growth of the aquaculture industry in countries
such as Thailand and Vietnam (particularly peneaid shrimp and
pangasius catfish, mainly striped river catfish, Pangasianodon
hypophthalmus) provides an opportunity for comparison of uti-
lization strategies to the European situation. In these Asian coun-
tries, producers and processors have developed in parallel and
traditionally use a mixture of high and low technology solutions
to utilize aquaculture production and processing coproducts (ac-
cording to stakeholders in the region). The relatively close collo-
cation of production, processing, and support industries in Asia
(particularly Vietnam) provide excellent opportunities to for-
mulate efficient resource use management strategies (Figure 3).
For the reasons above, these strategies may be logistically more
difficult to implement retrospectively in Europe.
Both Vietnam and Thailand are major producers and ex-
porters of penaeid shrimp. In 2007, Vietnam produced 376,700
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Figure 3 Production and number of processors of a) Pangasius catfish and penaeid shrimp in the Mekong delta of S. Vietnam in 2008b) Penaeid shrimp in S.
Thailand in 2007. Source: (VASEP 2010, VIFE 2009, Department of Fisheries (Thailand) 2009.
tons of shrimp, a 10-year increase of over 700%, whereas
Thailand produced 501,000 tons which was an increase of more
than 120% over 10 years (FAO, 2009b). Thailand remains the
biggest exporter of shrimp, exporting almost 374,000 tons in
2010 mainly to the United States of America with around 40%
of this preserved or prepared as value-added products such as
ready meals or gourmet products (Thai Frozen Foods Associa-
tion, 2009).
Evidence from processors in Thailand and the Mekong delta
show that there is a large variety of shrimp export products rang-
ing from whole to completely peeled and deheaded, for which,
complete data were not available. These are raw or cooked but
also include partially deshelled and value added. The variety of
shrimp products and the changing market makes the amount of
coproduct available difficult to assess, although for Vietnam it
is estimated at over 150,000 tons (Trang, 2010). Evidence from
VASEP (2010) suggests around half of Vietnamese shrimp is
being exported whole, mainly to Japan, the United States of
America and Europe. Estimates of fillet yields from peneaid
shrimp vary but most reliable figures suggest around 50% of the
animal is fillet (Table 1) for all species (Benjakul et al., 2009).
The vast majority of shrimp mortality occurs in the early stages
when the animals are less than 1 g, therefore they tend to be left
in the pond and are of little value.
In Vietnam, production of the pangasius catfish has grown
from 23,000 tons in 1997 to 1.15 million tons in 2008 (VASEP,
2010). As a consequence, support and fish processing industries
have grown rapidly with over 90% of production processed
locally for export to over 100 countries as frozen fillets (Lam
et al., 2009). However, the expanding industry has also expe-
rienced some of the same problems that the salmon industry
faced two decades ago. Disease has been a major issue for fish
production, resulting in high mortality and consequent use of
antibiotics (Lam et al., 2009). Pangasius catfish farms in An Gi-
ang province, one of the most intensive production areas on the
Mekong delta, commonly report a mortality of up to 30% in the
early-to-mid stages of the production cycle, which subsequently
drops to around 10% in the later stages of production, despite
a reliance on antibiotic-based therapies (Lam et al., 2009).
Possible contaminants in mortality flesh from therapeutants
may limit the opportunities for value addition, even for pet and
fur animal feeds (Nguyen et al., 2006; Lam et al., 2009). Fillet
yield for pangasius catfish is low compared to salmon, typically
ranging between 30 and 40% (Table 1), depending on the cut.
According to some processors, demand is growing for products
such as frozen industrial block, regular cuboid blocks which
can be further processed more easily. This process results in
more trimmings which could be used for many value addition
Key informant interviews of pangasius catfish processors in
Dong Thap and Can Tho provinces in the Mekong region, cou-
pled with direct observation in local markets in Soc Trang, su-
permarkets, and restaurants in several other Mekong provinces
revealed that postfilleting products are commonly on sale for
consumption. These included the catfish stomachs and heads.
According to Nguyen (2010), this is around 5% and the rest is
processed into fishmeal and oil, including viscera, heads, skins,
and trimmings (Le Nguyen, 2007). Fifty-three percent (53%)
of fish meal from coproducts is directed to terrestrial livestock
feeds, and 45% for domestic aquaculture, with the oils sepa-
rated for further sale (Nguyen, 2010). However, traceability can
sometimes be lost (Le Nguyen, 2007) possibly resulting in in-
traspecies feeding of exported products. Tacon (2002) suggested
that some shrimp coproduct may still be used to produce shrimp
feed and is preferred by some farmers. Although these coprod-
ucts provide a readily available protein supply for livestock,
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Tab l e 2 Summary of EU by product categories and regulations on their uses. See below for descriptions of various processes allowable under ABPR
Category Byproduct Allowable uses under ABPR
1. No fish byproducts in Cat. 1
2. Fish farm mortalities irrespective of cause
Fish parts collected from the effluent of Cat. 2 processing plants
Fish parts that contain excessive amounts of veterinary residues
Cat.3 material that may have been contaminated with Cat. 2.
Incineration on site or at approved facilities
Processed in accordance with other ABPR provisions but not for
livestock feeds, cosmetics or medicinal uses
Feeds for fur, zoo and circus animals
Ensiled, composted or used in biogas plants, meeting hygiene and
biosecurity measures in the annexes of the ABPR
Disposed of in landfill if special derogations are applicable
3. Parts of slaughtered animals considered unfit or not intended for
human consumption
Fish caught for fishmeal production
Coproducts from fish processing plants
Incineration on site or at approved facilities
Ensiled, composted or used in biogas plants, meeting hygiene and
biosecurity measures in the annexes of the ABPR
Processed in accordance with other ABPR provisions including
“technical purposes” such as pharmaceuticals and cosmetics
Used to make livestock feeds but must not be made into fishmeal
for feeding fish unless from wild sources
Source: European Commission 2002, 2003.
they could perhaps be redirected to other industries providing
products of more value.
Some farmers also revealed that fresh mortalities may some-
times be consumed by farm employees or sold to local markets.
While this would be highly unacceptable in the European Union,
it is commonly accepted in Vietnam but it is thought that in most
cases mortalities are being buried. According to evidence from
stakeholders, occasionally, mortalities were reported to be fer-
mented for fertilizer for use on local farms or on the site itself
in small quantities for fruit production.
The further consumption, processing, recycling, transport,
and traceability of aquaculture coproducts, byproducts, and
mortalities from aquaculture and capture fisheries within
the EEA is controlled by the European Animal By-Product
Regulations (ABPR)1and subsequent amendments2(European
Commission, 2002, 2003). These regulations control the use of
animal products which are not intended for human consumption
in order to maintain biosecurity, eliminate contamination of
food and animal feed, and maintain general hygiene. In
particular, they forbid the use of coproducts from cultured
fish processing in the manufacture of fishmeal for the feeding
of other cultured fish, even of different species (European
Commission, 2003). This is because of fears over transmissible
spongiform encephalopathies (TSEs). The byproduct categories
and their allowable uses are summarized in Table 2. There
have been suggestions that the ABPR are inappropriate for
aquaculture (Thistle Environmental Partnership, 2008) as
there is no evidence of TSEs within fish (FAO, 2002b) and
catastrophic mortalities due to nondisease events could perhaps
be better utilized if there were no biosecurity risks. In addition,
1ABPR, Regulation (EC) No 1774/2002
2Regulation (EC) No 811/2003
ABPR do not definitively state at what point postfilleting
products become coproducts or byproducts, not intended for
human consumption. There are many parts of the fish that
could be directed to human consumption at the filleting stage
including cheeks, bellies, and other off-cuts (Ram´
ırez, 2007).
Category 3 byproducts, including coproducts from fish pro-
cessing, have many more options open to their use than Cate-
gory 2 products, such as fish mortalities. At present, Category
3 coproducts can be used in nonfin fish feeds and for human
pharmaceuticals which Category 2 coproducts cannot. In addi-
tion to feeds for animals not intended for human consumption,
ABPR Category 2 or 3 material may be incinerated, composted
in closed containers or used in a biogas production plant (anaer-
obic digestion) but must meet other criteria stipulated in the
ABPR (European Commission, 2002). See Table 2.
From stakeholder and key informant interviews in Vietnam,
regulations in many Asian countries seem to be less strict or
at least less strictly enforced, and there is often a more ad
hoc approach to waste disposal and coproduct use. Certifica-
tion schemes are beginning to acknowledge these issues such
as the WWF Aquaculture Stewardship Council dialogues on
production standards (WWF, 2008, 2009, 2010). Coupled with
regulations imposed by importing nations local regulations may
be tightened and more strictly enforced. If the WWF standards
are widely adopted, the future intraspecies use of processing co-
products for feeds will be strictly prohibited whereas disposal
of catfish mortalities will be limited to fertilizing or “fermenta-
tion,” as well as the European method of incineration or burial
(WWF, 2009). While this may improve traceability and biose-
curity overall, some resource efficiency may be lost until more
technologically advanced solutions are available.
As the EU ABPR do not allow for mortalities to enter the
human food chain, their disposal options are not discussed here
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Tab l e 3 Summary of costs, level of expertise, and value addition from options available to mortalities falling into Category 2 of the ABPR
Level of Level of Operating Value of Pathogen
Method capital investment expertise costs product deactivation Comments
Ensiling1Low Low Low Very low Some Interim storage
Feeding to animals2Low Low Low Low If cooked Quality can be too poor
Onsite incineration3Low Low Medium None Yes High air pollution
Landfill3None Low High None No Biosecurity risk
Composting4Low Medium Low Low Yes Unsuitable for large numbers
Anaerobic digestion5High High Low High Thermo-phillic only Markets not well established
for liquid products
Source: 1. Arason et al., 1990; Carswell et al., 1990; Smail et al., 1993; L¨
adt, 2008, 2. Thistle Environmental Partnership 2008; 3. Glanville et al., 2006;
Thistle Environmental Partnership 2008; Local Government association 2008, 4. Glanville et al., 2006; Smail et al., 2009; Inter Trade Ireland 2009, 5. Seafish,
2008; He, 2010; M´
endez-Acosta et al., 2010; Inter Trade Ireland 2009.
in detail, although a summary of available options can be seen in
Table 3. Ensiling is often used to store farm mortalities and also
postfilleting coproduct before transportation for further process-
ing. Ensiling usually involves maceration and storing in plastic
containers, using organic acids at about 2 to 3% v/v to encour-
age autolytic hydrolysis, for interim storage before further treat-
ment or disposal. The process prevents spoilage and odours, and
avoids attracting vermin (Arason et al., 1990; Carswell et al.,
1990; L¨
adt, 2008). Ensiled product using organic acids can
be used as pig and other livestock feeds (Carswell et al., 1990;
adt, 2008) but acceptance from these industries can be
low (Arason et al., 1990). Organic acids are generally preferred
in all countries, not only because they can be fed to animals,
but because they are less corrosive to equipment and less dan-
gerous to handle than inorganic acids (Carswell et al., 1990).
The product can also be used as a fertilizer if used with other
ingredients (Prescott et al., 1997). These options may also be
useful for Category 3 coproducts in remote locations, for exam-
ple, where higher value addition options may not be feasible.
Ensiling is not generally used as a storage method of shrimp but
Cao et al. (2009) showed that it could be used to extract protein
from coproducts for further use.
Fish and Shrimp Meals
Aquaculture has often been condemned for its use of com-
mercial fisheries products in aquafeeds, although its use in
aquaculture has not increased significantly for the last 10 years
(Figure 1). However, global supply is unstable and has led to in-
creasing prices on the global market (FAO, 2009b). The burden
on the fishmeal industry can, therefore, be lessened by supply-
ing coproducts from aquaculture for use in terrestrial livestock
feeds, which would normally be sourced from the reduction in-
dustries. Pig and poultry feeds include reduction fishmeal, con-
taining between 6 and 10% oil (Seafish, 2009b), because of the
health benefits of omega-3 FAs to both the livestock and human
consumers (see below) (Fishmeal Information Network, 2001;
Kouba and Mourot, 2010). Though pangasisus catfish are natu-
rally high in protein, they are low in omega-3 (Polak-Juszczak,
2007), meaning in Vietnam relative performance of livestock
may be better with a fishmeal source high in omega-3. Nguyen
(2010), showed that pigs fed diets containing catfish coproduct
performed well or better in terms of diet intake, growth, meat
quality, and mortality, than diets which included traditional fish
meal sources but commercial data is not available. Figure 5
shows the main methods currently employed in coproduct uti-
lization for the named species.
Although the EU ABPR forbid the use of farmed fish co-
products in fin-fish feeds, the regulations will apparently allow
them to be used in shrimp diets or vice versa. Studies have
shown that capture fishery coproducts can be used in shrimp
feeds with good results (e.g., Sudaryono et al., 1996). Use of
fin-fish byproducts from capture fisheries have also been used in
trials for aquafeeds for other fin-fish species by Goddard et al.
(2008), Whiteman and Gatlin (2005) and Seoka et al. (2008)
amongst others. The results for these studies were mixed.
Shrimp meal has been shown to perform less well than fish-
meal when included in aquafeeds (e.g., Hardy et al., 2005;
Whiteman and Gatlin, 2005). This is attributed to poor avail-
ability of protein (Coward-Kelly et al., 2006; Sachindra et al.,
2006). Although shrimp coproduct has protein levels of 35 to
50%, much is bound to highly indigestible chitin (15 to 25% dry
weight) (Edwards, 2004; Sachindra et al., 2006) and 10 to 15%
as minerals (Sachindra et al., 2006). Digestibility can often be
improved by separation of the chitin by hydrolysis or fermen-
tation (Nwanna, 2003; Coward-Kelly et al., 2006). Autolysis at
ambient temperatures has generally given low yields of usable
products. However Cao et al. (2009) showed that autolysis of
shrimp heads using gradual increase in temperature up to 70C
could give protein recovery rates of 88.8%, which can then be
used for animal feeds or flavorings for human consumption (see
Fish Oils
In recent years, there has been much emphasis on the health
benefits of consuming oily fish as part of a balanced diet,
not least because of high omega-3 polyunsaturated fatty acid
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Figure 4 Main routes for utilisation of processing co-products from cultured Atlantic salmon, Pangasius catfish and peneaid shrimp currently employed in the
EEA and SE Asia. Source: Le Nguyen 2007; SEPA 2004 and Stakeholder interviews in the Mekong Delta, Vietnam and S. Thailand.
(PUFA) contents, eicosapentaenoic acid (EPA), and docosohex-
aenoic acid (DHA) which are limited to marine sources. Studies
have shown that maintaining a level of omega-3 to be impor-
tant in reducing factors associated with heart disease (Holub
and Holub, 2004; Domingo, 2007), strokes, thrombosis, mental
health problems and arthritis (Sun et al., 2002). More recently a
high ratio of omega-3 FAs (including EPA and DHA) to inflam-
matory omega-6 fatty acids, common in many plant oils, has also
shown to be important in human health, particularly in prevent-
ing coronary heart disease (Holub and Holub, 2004). In animal
nutrition, inclusion of long chain omega-3 in pig diets has been
shown to improve survival substantially for weaning and suck-
ling pigs and is, therefore, an important dietary component (Fish
Information Network, 2001). At present much of this omega-3
comes from commercial fishmeal (Seafish, 2009b). However, if
necessary, fishmeals with low omega-3 content from pangasius
catfish coproducts, for example, could be supplemented with
oils extracted from salmonid coproduct or other high omega-3
Concentrations of lipid and in turn of EPA and DHA in
farmed salmon viscera are higher than those of the fillet (Sun
et al., 2006), and of many wild captured fish (Figure 4), although
this will depend on the diet of the farmed salmon. A propor-
tion of Scottish salmon, perhaps 10%, are fed higher levels
of fishmeal and fish oil than in other locations to meet con-
sumer demand (Tacon and Metian, 2008). Consumer fears over
Figure 5 EPA and DHA concentrations in the viscera of farmed Atlantic salmon, compared with whole wild and farmed salmon and other commercially
important species. (See Table 1 for total lipid and omega-3 contents in the studied species). Adapted from Sun et al. 2006.
Downloaded by [University of Stirling Library], [Richard Newton] at 07:35 21 November 2013
contamination in farmed salmon with persistent organic pollu-
tants (Hites et al., 2004) and heavy metals (Domingo, 2007)
may lead to further fears over bioaccumulation if oils are con-
centrated for health supplements or recycled for animal feeds.
Contaminant levels are generally regarded as being below lev-
els considered to be dangerous to human health (COT, 2006;
Fernandes et al., 2009) and often the refining process removes
many persistent contaminants (Muggli, 2006), especially the
deodorization process using steam distillation, but this may de-
stroy valuable fractions such as carotenoids (Hilbert et al., 1998).
Salmonid visceral oil is of lower quality than that of muscle’s
in terms of lower phospholipids, antioxidants α-tocepherol, and
total carotenoid concentrations (Zhong et al., 2007) but despite
this, visceral oil is less subject to oxidation than muscle oils
(Sun et al., 2006) and aquaculture coproducts can often be sup-
plied fresh (ˇ
e et al., 2009). Oils are already extracted from
salmon coproducts by simple heating, decanting, and clarifica-
tion by centrifuge, in Denmark by Hordafor, Norway by Scanbio
Ltd., and the United Kingdom by Rossyew Ltd. who also filter
the oil for a purer product. However, the full potential is not
being met. More research is required to determine the markets
for the products and where oils can best be directed. Also, yields
can be improved and the omega-3 fraction separated to higher
purity (Sun et al., 2002) although this may not be cost effective.
Whereas it is important to maximize the use of omega-3 FAs
to relieve the burden on commercial fishmeal and oil reduction
industries, the low omega-3 content in pangasius catfish fat may
mean that other industrial uses may be more appropriate. If cost
effective, these applications can also contribute to resource effi-
ciency of fishmeal and other global inputs within and without the
pangasius catfish value chain. Fish oils have traditionally been
used in the tanning industry for the production of high quality
leather such as chamois, and this is a possible route for oils
produced from mortalities (Thistle Environmental Partnership,
2008). Worldwide, there has been increasing interest in biofuels
as an alternative to fossil fuels, but this has been tempered with
concerns over deforestation and diversion of food products to-
ward the biofuel industry (Sachs, 2007; Piccolo, 2009). Recent
activities have shown catfish coproducts in Vietnam and tilapia
coproducts in Honduras to produce excellent biofuels. Research
into using fish coproducts and mortalities from the pangasius
catfish industry has been gathering pace (Nguyen D.A.T. et al.,
2009; Nguyen T.V. et al., 2009; Piccolo, 2009). Fish oils have
been reported to be excellent fuels because they can be used
in unmodified diesel engines and a high yield can be obtained
from the raw product (Piccolo 2009). Initial attempts produced
fuels which released emissions which were harmful to human
health, but the quality has now improved (Nguyen D.A.T. et al.,
Fish fat can be broken down into functional biofuels by sim-
ple processes on small or large scales with glycerine as a fur-
ther coproduct that has applications in a number of industries,
e.g., cosmetics (Piccolo, 2009). The oils may be further puri-
fied into fuels of more specific character and use as outlined by
Wiggers et al. (2009), Wisniewski Jr. et al. (2009), and Preto
et al. (2007), and which may meet European Quality Standards
for biofuels, although this needs further attention. According to
Nguyen D.A.T. et al. (2009), between 2005 and 2007 the price
of pangasius catfish fat increased from between 2,000 and 3,000
VND (US$0.10 to $0.14) per kg to about 6,000 VND ($0.28)
per kg due to interest in producing biofuels and there are now
established processing plants in An Giang and Can Tho. The
Can Tho plant has a capacity of around 50 tons per day of raw
material and was exporting its product to Singapore at 11,000
VND (about US$0.60) per liter in 2005 (, 2009).
Although there is no specific mention of using mortalities or fish
coproducts for biodiesel production in the EU ABP regulations,
the allowance for biogas production and industrial uses should
permit this route which could be of particular interest to remote
or small scale fish-farms and processors in the EU.
Sauces, Pastes and Other Products for Human Consumption
In Europe and other Western countries, direct consumption
options for humans are likely to be limited because of customer
perception, compared to Vietnam and other Asian countries
which import processing coproducts from the West for human
consumption. It is difficult to trace the coproducts, which are
available for value addition from European salmon because of
the diffuse nature of processing and, therefore, the various frac-
tions in each of the major processing countries. The accept-
ability of products to European consumers may differ to their
Asian counterparts and the nature of value-added products will
depend on the quality of the flesh which can be obtained from
the trimmings, etc., and may only allow for commodities such
as fish-balls, mousses or pˆ
es to be produced (Young, 2010
personal communication).
In Thailand, Vietnam, and many other Asian countries, uti-
lization of shrimp coproducts from small capture fishery species
such as krill is fairly well established as fermented goods for
human consumption (Sobhi et al., 2010). There is also an es-
tablished market for mungoon, a shrimp paste made from the
cephalothorax (Binsan et al., 2008). Mungoon is a highly nu-
tritious and healthy food because of high omega-3 FAs, essen-
tial amino acids and calcium ions according to (Binsan et al.,
2008). Despite this usage, the yield of mungoon using traditional
production methods is low, reported at 21.5% of raw material
(Benjakul et al., 2009), leaving substantial amounts of further
coproduct that requires further processing into useful products
or disposal.
In Vietnam, most Pangasius catfish production is directed
toward frozen fillets, but there is also a market for fish sauces,
pastes, and surimi to which some coproducts, such as trimmings
and undersize fish, are directed (Le Nguyen, 2007). Gelman et al.
(2001) and Glatman et al. (2000) described possible techniques
for fermenting fish, using strains of lactic acid bacteria, similar
to the traditional techniques for mungoon, to produce novel
“meat-like” products which could be acceptable to consumers.
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Collagen and Gelatin
Collagens are the most abundant proteins in vertebrates, com-
monly found in connective tissues, especially of the skin but also
bones. There are at least 26 forms (Li et al., 2005) of which the
most abundant and most useful for biomedical and cosmetic
applications is type I (Lee et al., 2001; Li et al., 2005). Its use-
fulness stems from the ease of its extraction in solution and that
it can be shaped into many forms containing tensile fibers which
are biodegradable, biocompatible, and nonantigenic (Lee et al.,
2001). These can be used in many applications including mul-
tiple medical uses such as drug delivery and wound dressings,
cosmetics, and edible food coatings (Lee et al., 2001; Singh
et al., 2011). Collagen extracted from fish swim-bladders, com-
monly called isinglass, has traditionally been used to clarify
beer, (Hickman et al., 2000; Regenstein and Zhou, 2007). Ex-
traction from terrestrial animals is well established, however fish
skins also provide excellent potential for extraction and has been
described by Singh et al. (2011), Sadowska and Kolodziejska
(2005), Muyonga et al. (2004), Aidos et al. (1999) and Eckhoff
et al. (1998) among others. Although yields from fish skins are
generally higher than mammalian (Yunoki et al., 2003), there are
differences in structure and amino/imino acid sequences which
can change the properties of fish collagens compared to higher
vertebrates. Denaturation temperatures are generally lower for
fish which may affect their uses, particularly for human biomed-
ical applications (Nagai and Suzuki, 2000; Yunoki et al., 2003,
2004; Saito et al., 2009), but more work is needed to investigate
how the different properties can best be applied. The thermal
stability of collagen is generally higher in tropical species and
according to Singh et al. (2011), pangasius catfish collagen has
a maximum temperature threshold of around 39.5C, similar
to that of commercial porcine collagen. Collagen with lower
thermal stabilities, such as that from salmon, reported as about
19C for chum salmon (Yunoki et al., 2003), can be improved
by techniques such as UV irradiation without risking toxicity
that chemical techniques may encounter (Yunoki et al., 2003).
In most extraction studies, fish collagen was split between
acid and pepsin soluble fractions. Singh et al. (2011) described
methods to extract collagen from pangasius catfish skins simi-
lar to other collagen extraction techniques, using NaOH to first
extract noncollagen proteins followed by neutralization and dis-
solving in acetic acid. The acid soluble collagen can then be
precipitated using NaCl and the further fractions obtained from
the filtrate using pepsin hydrolysis to give a combined yield of
12.8% (wet skin weight).
Gelatin is a mixture of proteins prepared from the breaking
of cross-linkages and denaturation of collagen but otherwise is
similar in amino/imino-acid composition to the parent collagen
(Regenstein and Zhou, 2007). Although less valuable per unit
weight, it has vast opportunities for halal and kosher food ap-
plications, most commonly in various sorts of gels for texture,
stabilization, emulsification, and alternatives to fats (Karim and
Bhat, 2009). Fish gelatins of cold and warm water fish, and
terrestrial sources have certain tradeoffs against one another.
Lower melting points of fish gelatins are an issue, and there-
fore those from warm water fish with higher melting points may
be of more value, possibly due to higher imino acid content
(Muyonga et al., 2004; Karim and Bhat, 2009; Shahiri
Tabarestani et al., 2010). However, a major application of
gelatins has been in chilled desserts which could perhaps fa-
vor lower melting point fish gelatins because of better release
of flavors and aromas (Choi and Regenstein, 2000; Boran et al.,
2010) and offer alternative product options because of different
textures and properties (Zhou and Regenstein, 2007). Some ad-
ditives such as neutral salts (Sarabia et al., 2000), sugars (Choi
and Regenstein, 2000), egg albumen (Badii and Howell, 2006) or
treatments with transglutaminase (Yi et al., 2006) may improve
properties but uncertainty exists over the kosher/halal status of
enzyme treatments (Karim and Bhat, 2009). Thermal stability
is of importance in the manufacture of drug and food supple-
ment capsules, which has been suggested as another possible
application for fish gelatins with lower melting points (Karim
and Bhat, 2009). Other applications include possible biomedical
uses such as biocompatible films and fibers with similar proper-
ties to collagen, possibly combined with other biopolymers such
as chitosan described below (Yi et al., 2006). The most desirable
qualities for all applications are high gel strength, viscosity, and
rheological properties, given particularly by the amino/imino
acid contents and lower content of low molecular weight frac-
tions (Eysturskarðet al., 2009; Karim and Bhat, 2009; Badii and
Howell, 2006) but also higher gelatin concentration and matu-
ration temperature, i.e., that at which the gel is allowed to set
(Choi and Regenstein, 2000). The intrinsic physical properties
also tend to be inferior for (especially cold water) fish compared
to mammalian sources, but the extraction process can also have
a significant influence over the quality of the gelatin (Boran
et al., 2010; Shahiri Tabarestani et al., 2010). Generally, it is
extracted by one of two processes, the acid or the alkaline pro-
cess, referring to the pretreatment phase, to produce type A or
type B gelatin, respectively. Low storage and pretreatment tem-
peratures are generally thought to preserve the integrity of fish
gelatin and provide better yields, especially of cold water ori-
gin which are subject to quicker degradation than mammalian
gelatin (Gim´
enez et al., 2005a; Regenstein and Zhou, 2007;
Karim and Bhat, 2009). Pretreatment is usually followed by
hydrolysis in mild organic acids at moderate temperatures of
around 45C(Gim
enez et al., 2005b; Karim and Bhat, 2009).
The alkaline process has advantages in removing more noncol-
lagenous protein and the following acid neutralization allows
for a weak acid extraction which minimizes damage and gives
high yields of good quality gelatin (Regenstein and Zhou, 2007;
Shahiri Tabarestani et al., 2010). Barriers to the production of
fish gelatins cited by Karim and Bhat (2009) were possible
fishy off-flavors and odors in some species, and problems with
availability of large amounts of consistent raw material, there-
fore economy of scale. If any problems of fishy flavor and odor
are sufficiently addressed, there is vast potential for collagen
and gelatin extraction from the pangasius catfish industry within
the Mekong delta which produces large amounts of consistent
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coproduct and has the infrastructure to provide fresh material
and overcome economy of scale difficulties. In Europe, niche
markets for cold water fish gelatins may be less interesting and
may not be able to compete with porcine or bovine sources.
Chitosan and Glusosamine
Chitosan is a polysaccharide which is most commonly made
from the deacetylization of chitin from crustacean shells but
must first be separated from the protein and mineral complex.
Chitosan is an attractive material because it is biodegradable,
biocompatible, exhibits antimicrobial and haemostatic prop-
erties, binds protein and fats, and is soluble in weak acids
(Shahidi, 2007). Chitosan has many commercial applications
depending on the properties provided by the raw material, the
processes used to achieve different degrees of deacetylization
(DD), the molecular weight of the product, and polyectrolytic
properties (Synowiecki and Al-Khateeb, 2003). Applications
include disease-resistant coatings for agriculture and maintain-
ing freshness of produce, in industrial polymers used for paper
and textiles, halal and kosher cosmetics, and medical purposes
such as wound dressings, slow-release drug, and encapsula-
tion technologies. It is also commonly marketed as a slim-
ming aid (Percot et al., 2003; Synowiecki and Al-Khateeb,
2003; Aye and Stevens, 2004; Coward-Kelly et al., 2006; Lalle-
mont, 2008). Commercial processes for its production from
aquaculture coproducts are already well established and usu-
ally involves treatment of shrimp shell with acids to deminer-
alize the calcium content, alkalis to separate the chitin from
the protein and finally deacetylization of the chitin to pro-
duce chitosan (Synowiecki and Al-Khateeb, 2003). Properties
given by high DDs are considered more valuable outlined by
Lertsutthiwong et al. (2002) and Synowiecki and Al-Khateeb
(2003) among others but this requires several deacetylization
steps with washing and drying between each, and high lev-
els of control at each point (Lallemont, 2008). The quantities
of chemicals used have caused environmental concerns (Aye
and Stevens, 2004; Pacheco et al., 2009; Trang, 2010) and can
adversely affect the product (Arment and Guerrero-Legarreta,
2009). Therefore, interest is toward techniques such as enzy-
matic hydrolysis which are potentially more predictable, less
damaging to the product and environment, and that separate
protein and carotenoid fractions for further use (Synowiecki
and Al-Khateeb, 2003; Aye and Stevens, 2004; Coward-Kelly
et al., 2006. More research is required to weigh the various
advantages and disadvantages over traditional methods on eco-
nomic and environmental basis (Synowiecki and Al-Khateeb,
2000; Percot et al., 2003).
The growth in shrimp culture has led to an increase in the
availability of raw material for chitosan production making it
more economically attractive (Coward-Kelly et al., 2006). Chi-
tosan production is low in Vietnam because of environmental
concerns and technological barriers relating to the quality of the
product (Trang, 2010). However, it exports a small proportion
of chitin and shell from shrimp processing to China for chitosan
production which is then further exported worldwide. Evidence
from interviews with Vietnamese shrimp processors also sug-
gests a growing chitin industry in Vietnam but it is losing the
potential to create huge revenues, as the price for chitosan is be-
tween $30 and $150 US per kg, compared to $3.60 and $6 per kg
for chitin (Pichyangkura, 2010). Thailand has a well-established
chitosan industry and dedicated research into its applications,
though more work is needed to establish these markets and as-
sess how they may compete with alternative products such as
collagen for some applications. Currently, around 70% of the
chitin produced is transformed into less valuable glucosamine
products, 10% into oligosaccharides and only 20% into chitosan
(Lallemont, 2008).
Glucosamine is a health supplement which is widely avail-
able in several forms in the United States and Europe. It is
marketed for alleviation for osteoarthritis as it is thought to pro-
mote the formation and repair of cartilage (Lallemont, 2008). It
is formed from the hydrolysis of chitin usually by the action of
acids. The process does not require the same level of control as
chitosan production, though it follows the same initial steps to
produce chitin which is then hydrolysed by the action of acids.
The accessibility of the technology and the developed interna-
tional markets result in it being more favored by industry than
chitosan, but this may change as more applications for chitosan
become apparent, particularly for valuable medical applications
mentioned above (Lallemont, 2008).
Fish and Shrimp Peptides
Hydrolysis techniques are well established in other indus-
tries and are gaining interest in the aquaculture and fisheries
industries for the abstraction of peptides from marine products.
The resulting mixture of peptides is referred to as a protein
hydrolysate. Peptide production by ensiling is unpredictable
(Cancre et al., 1999) because of many different endogenous en-
zymes, and the low pH may destroy some valuable nutritional
elements (Lian et al., 2005) leading to bitter tasting peptides
with unpredictable properties that may be unsuitable for many
applications (Hevrøy et al., 2005). Therefore, more predictable
and controllable forms of hydrolysis are required for the produc-
tion of peptides of particular size and character, which determine
specific properties (Hevrøy et al., 2005; Bourseau et al., 2009;
Vandanjon et al., 2009). This requires commercially available
enzymes in controlled conditions which can give more pre-
dictable results than endogenous enzymes. There are a huge
number of applications for fish protein hydrolysates including
bio-active supplements, health food supplements, food addi-
tives (e.g. emulsifiers and foaming agents), animal feeds and
cosmetics outlined by Thorkelsson and Kristinsson (2009) and
Kristinsson and Rasco (2000) among others. Valuable peptides
can be extracted from fish heads, trimmings, bones, viscera,
shrimp shells, and heads. The processes have been well studied,
but documentation and verification of health claims, with regard
to rigorous in vivo investigation and many marketing aspects to
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achieve full commerciality still need to be addressed (Raghavan
and Kristinsson, 2009; Thorkelsson and Kristinsson, 2009).
The properties given by various peptides is huge and beyond
the scope of this review but smaller peptides (of high degrees of
hydrolysation) are generally more desirable for flavorings and
larger peptides for foaming agents and emulsifiers (Kristinsson
and Rasco, 2000; ˇ
e 2009). The effect that various condi-
tions have on the size and character of final products of some
fish hydrolysates and their uses is outlined by Bourseau et al.
(2009), Cancre et al. (1999), Kristinsson and Rasco (2000),
Thorkelsson and Kristinsson (2009) and Kim and Mendis
(2006). Human health benefits of fish peptides are generally
attributed to high antioxidative properties (Dong et al., 2008)
and are given by He et al. (2007), Hong and Secombes (2009),
Je et al. (2004), and Marchbank et al. (2009) among others.
Methods of filtration and separation for purifying hydrolysates
are given by Bourseau et al. (2009), Vandanjon et al. (2009),
and Thorkelsson and Kristinsson (2009).
There are many publications which investigate the feasibil-
ity of feeding hydrolysates from fish and seafood coproducts to
fin-fish aquaculture species (Gildberg et al., 1995; Hevrøy et al.,
2005; Aksnes et al., 2006) among others and shrimp (C´
Murueta and Garc´
no, 2002) with varying success. This
poses many opportunities for value addition, but strict biosecu-
rity and traceability measures would be necessary. Salmon hy-
drolysates and protein concentrates are already produced com-
mercially in conjunction with oils, by the companies mentioned
above, for use in the animal feed industry.
Carotenoids (Astaxanthin and Canthaxanthin)
Shrimp and salmonid coproducts also contains significant
amounts of carotenoid, mostly astaxanthin or canthaxanthin at
around 24 g per ton in cultured P. monodon (Babu et al., 2008)
and up to 7.5 g per ton in salmon viscera (Czeczuga et al., 2005).
Carotenoids are powerful antioxidants and, therefore, have many
beneficial properties in human and animal nutrition (Lorenz
and Cysewski, 2000; Pacheco et al., 2009). It is also used as a
pigment in cosmetics (Armenta and Guerrero-Legarreta, 2009).
Synthetic astaxanthin is used as a pigment in animal
feeds, particularly for salmonids (Lorenz and Cysewski, 2000;
Sachindra et al., 2006) at about 5 kg per ton (Synowiecki and
Al-Khateeb, 2003) as flesh color is important for salmonid mar-
keting. However, no significant difference was found between
uptake and deposition of synthetic astaxanthin and natural astax-
anthin in salmonid feeds (Lorenz and Cysewski, 2000). There-
fore, natural astaxanthin has no advantage within aquafeeds and
is unlikely to be able to compete with synthetic ingredients, al-
though there could be a niche in the organic aquafeed market.
However, concentrations are far less than in the alga Haema-
tococcus pluvialis, which commercially grown can contain as
much as 30 kg per ton (Guerin et al., 2003). Therefore, extrac-
tion of astaxanthin from shrimp and salmonid coproducts is only
likely to be cost-effective if it is removed during the processing
of other valuable products, but it may be able to add value to
salmon oil health supplements if retained during the extraction
Extraction can be combined with chitosan production
opez et al., 2002) and some studies have shown that
acids, commonly used in the chitosan industry, may increase
the yield of astaxanthin because of reduced oxidation. However,
excessively aggressive acid and alkali treatments can adversely
affect the carotenoid (Armenta-L´
opez et al., 2002; Sachindra
and Mahendrakar, 2005; Sachindra et al., 2006; Pacheco et al.,
2009). Most promising methods, both economically and envi-
ronmentally, therefore, are those which can combine mineral,
chitin, protein, oil, and carotenoid separation and extraction in
the various processes outlined above (Armenta-L´
opez et al.,
2002; Synowiecki and Al-Khateeb, 2003; Coward-Kelly et al.,
2006; Pacheco et al., 2009).
Natural astaxanthin of 60 capsules containing around 4 mg
from H. pluvialis commonly sell for around US$20 on the In-
ternet, therefore there is commercial potential for natural sub-
stance from a number of aquaculture sources including shrimp
and salmon coproduct.
Aquaculture coproducts are under-utilized in many parts of
Europe resulting in lost profits and potential environmental im-
pact through waste disposal. In Asia, coproducts are used for
production of value-added commodities but probably not to
their full economic potential. In addition, their current utiliza-
tion could be posing risks to the environment, human health,
and biosecurity.
Aquaculture coproducts have the potential to supply quality
fishmeal and oils to terrestrial livestock feeds, thus alleviating
some of the pressure on the reduction industries. They may
also be directed toward food additives, high-value health sup-
plements, and cosmetic industries that are acceptable to most
religious groups, in some cases providing a lucrative side in-
dustry. They have significant advantages over capture fishery
coproducts in that they can be supplied fresh and in a consistent
form. However, for many, further research is needed to sup-
port medical claims and develop markets for their full economic
potential to be met.
With regard to aquaculture mortalities, ABPR has proven
a barrier in many circumstances. However, research has shown
that there are other uses for mortalities which have greater biose-
curity and are kinder to the environment, reducing impacts and
burdens on resources. These strategies may not only reduce costs
but provide income if logistical and legislative barriers are over-
come. More research is required to evaluate these different tech-
nologies for resource efficiency in economic and environmental
terms. There are many economic and environmental assessment
tools which could do this such as standard Cost Benefit Analy-
sis approaches in conjunction with Life Cycle Assessment and
other environmental impact modeling tools.
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This project forms part of the EU-funded SEAT Project3
(Sustaining Ethical Aquaculture Trade). The authors would like
to thank the staff of Kasetsart University, Thailand, and Can
Tho University, Vietnam departments of fisheries SEAT project
teams for help in organizing field trips to aquaculture and pro-
cessing facilities, data collection, translation, and understanding
of the Asian situation.
REFERENCES (2009). Dusinhho
.c-Sn phmtrinvo
.ng xut khuca
DBSCL. Available from
80%93-san-pham-trien-vong-xuat-khau-cua-dbscl/. (In Vietnamese).
Aidos, I., Lie, Ø. and Espe, M. (1999). Collagen content in farmed Atlantic
salmon (Salmo salar L.). J. Agr. Food Chem. 47:1440–1444.
Aksnes, A., Hope, B., J¨
onsson, E., Bj¨
ornsson, B. T. and Albrektsen, S. (2006).
Size-fractionated fish hydrolysate as feed ingredient for rainbow trout (On-
corhynchus mykiss) fed high plant protein diets. I: Growth, growth regulation
and feed utilization. Aquaculture.261:305–317.
Alder, J., Campbell, B., Karpouzi, V., Kaschner, K., and Pauly, D. (2008). Forage
fish: From ecosystems to markets. Ann. Rev. Environ. Resour.33:153–166.
Arason, S., Thoroddsson, G. and Valdimarsson, G. (1990). The production of
silage from waste and industrial fish: The Icelandic experience. International
By-Products Conference, April (1990), Anchorage, Alaska.
Armenta, R. E. and Guerrero-Legarreta, I. (2009). Amino acid profile and en-
hancement of the enzymatic hydrolysis of fermented shrimp carotenoproteins.
Food Chem. 112:310–315.
opez, R., Guerrero, L. and Huerta, S. (2002). Astaxanthin extraction
from shrimp waste by lactic fermentation and enzymatic hydrolysis of the
carotenoprotein complex. J. Food Sci. 67(3):1002–1006.
Aye, K. and Stevens, W. (2004). Technical note: Improved chitin production by
pretreatment of shrimp shells. J. Chem. Technol. Biotech. 79:421–425.
Babu, C. M., Chakrabarti, R. and Sambasivarao, K. R. S. (2008). Enzymatic
isolation of carotenoid-protein complex from shrimp head waste and its use
as a source of carotenoids. LWT- Food Sci. Technol. 41:227–235.
Badii, F. and Howell, N. K. (2006). Fish gelatin: Structure, gelling proper-
ties and interaction with egg albumen proteins. Food Hydrocolloids. 20:
Bansback, B. (2006). Independent review of the Fallen stock scheme and
company. Available from:
Benjakul, S., Binsan, W., Visessanguan, W., Osako, K. and Tanaka, M. (2009).
Effects of flavourzyme on yield and some biological activities of mun-
goong, an extract paste from the cephalothorax of white shrimp. J. Food
Sci. 74(2):73–80.
Bimbo A. P. (2007). Current and future sources of raw materials for the long-
chain omega-3 fatty acid market. Lipid Technol. 19(8):176–179.
Binsan, W.,Benjakul, S., Visessanguan, W., Roytrakul, S., Faithong,N., Tanaka,
M. and Kishimura, H. (2008). Composition, antioxidative and oxidative sta-
bility of mungoon, a shrimp extract paste from the cephalothorax of white
shrimp. J. Food Lipids. 15:97–118.
Boran, G., Lawless, H. T. and Regenstein, J. M. (2010). Effects of extraction
conditions on the sensory and instrumental characteristics of fish gelatin gels.
J. Food Sci. 75(9):469–476.
Borch, O.-J. (1999). New organizational forms within the aquaculture indus-
try: The fishfarming enterprise as a ‘virtual’ organization. Aquacul. Econ.
Manage. 3(2):105–120.
Bourseau, P., Vandanjon, L., Jaouen, P., Chaplain-Derouiniot, M., Mass ´
e, A.,
erard, F., Chabeaud, A., Fouchereau-P´
eron, M., Le Gal, Y., Ravallec-
e, R., Berg´
e, J.-P., Picot, L., Piot, J.-M., Batista, I., Thorkelsson, G.,
Delannoy, C., Jakobsen, G. and Johansson, I. (2009). Fractionation of fish
protein hydrolysates by ultrafiltration and nanofiltration: Impact on peptidic
populations. Desalination. 244:303–320.
Briggs, M., Funge-Smith, S., Subasinghe, R. P. and Phillips, M. (2005). In-
troductions and Movement of Two Penaeid Shrimp Species in Asia and the
Pacific. FAO Fisheries Technical Paper 476, FAO, Rome.
Cancre, I., Ravallec, R., Van Wormhoudt, A., Stenberg, E., Gildberg, A. and
Le Gal, Y. (1999). Secretagogues and growth factors in fish and crustacean
protein hydrolysates. Mar. Biotech. 1:489–494.
Cao, W., Zhang, C., Hong, P., Ji, H., Hao, J. and Zhang, J. (2009). Autolysis of
shrimp head by gradual temperature and nutritional quality of the resulting
hydrolysate. LWT - Food Sci. Technol. 42:244–249.
Carswell, B., Willow, K. and Ekkart, J. (1990). Ensiling Salmon Mortalities:
Suggested Guidelines for B.C. Farmers. Aquaculture Industry Development
Report 90-3. Ministry of Agriculture and Fisheries, Aquaculture and Com-
mercial Fisheries Branch, British Columbia, Canada.
Choi, S.-S. and Regenstein, J. M. (2000). Physicochemical and sensory charac-
teristics of fish gelatin. Food Chem. Toxicol. 65(2):194–199.
COT. (2006). Statement on organic chlorinated and brominated contami-
nants in shellfish, farmed and wild fish. Available from
Coward-Kelly, G., Agbogbo, F. and Holtzapple, M. (2006). Lime treatment
of shrimp head waste for the generation of highly digestible animal feed.
Bioresource Technol. 97:1515–1520.
ordova-Murueta, J. H. and Garc´
no, F. L. (2002). Nutritive value
of squid and hydrolyzed protein supplement in shrimp feed. Aquaculture.
Czeczuga, B., Czezuga-Semeniuk, E. and Vala Tyggvadottir, S. (2005).
Carotenoid content in various body parts of Atlantic salmon (Salmo salar
L.) and Arctic charr (Salvelinus alpinus L.) specimens from an ocean ranch-
ing farm. In: Oceanological and Hydrobiological Studies Vol. XXXIV(1),
pp. 31–42. Institute of Oceanography, University of Gda ´
nsk, Poland.
De Silva, S. and Turchini, G. (2008). Towards understanding the impacts of the
pet food industry on world fish and seafood supplies. J. Agr. Environ. Ethics
Department of Fisheries (Thailand). (2009). Fisheries Statistics Thailand 2007.
No. 5/ (2009). Information Technology Center, Department of Fisheries,
Ministry of Agriculture and Cooperatives, Bangkok, Thailand.
Domingo, J. L. (2007). Omega-3 fatty acids and the benefits of fish Consump-
tion: Is all that glitters gold? Environmen. Int. 33:993–998.
Dong, S., Zeng, M., Wang,D., Liu, Z., Zhao, Y. and Yang, H. (2008). Antioxidant
and biochemical properties of protein hydrolysates prepared from Silver carp
(Hypophthalmichthys molitrix). Food Chem. 107:1485–1493.
Eckhoff, K., Aidos, I., Hemre, G.-I. and Lie, O. (1998). Collagen content in
farmed Atlantic salmon (Salmo salar, L.) and subsequent changes in solubility
during storage on ice. Food Chem. 62(2):197–200.
Edwards, P. (2004). A Survey of Marine Trash Fish and Fish Meal as Aquacul-
ture Feed Ingredients in Vietnam. Working paper no. 57. Australian Centre
for International Agricultural Research, Canberra, Australia.
Einen, O. and Roem, A. J. (1997). Dietary protein/energy ratios for Atlantic
salmon in relation to fish size: Growth, feed utilization and slaughter quality.
Aquacult. Nutr. 3:115–126.
European Commission. (2002). Regulation (EC) No 1774/(2002) of the Euro-
pean Parliament and of the Council, laying down health rules concerning
animal by-products not intended for human consumption.
European Commission. (2003). Commission Regulation (EC) No 811/(2003),
implementing Regulation (EC) No 1774/(2002) of the European Parliament
and of the Council as regards the intra-species recycling ban for fish, the
burial and burning of animal by-products and certain transitional measures.
Eysturskar, J., Haug, I. J., Ulset, A.-S. and Draget, K. I. (2009). Mechani-
cal properties of mammalian and fish gelatins based on their weight aver-
age molecular weight and molecular weight distribution. Food Hydrocolloid.
Downloaded by [University of Stirling Library], [Richard Newton] at 07:35 21 November 2013
FAO. (2002a). The State of the World Fisheries and Aquaculture (2002). FAO,
Rome, Italy.
FAO. (2002b). Use of Fishmeal and Fish Oil in Aquafeeds: Further Thoughts
on the Fishmeal Trap. Fisheries circular 975. FAO, Rome, Italy.
FAO. (2009a). The State of World Fisheries and Aquaculture 2008. FAO, Rome,
FAO. (2009b). Fishstat Aquaculture 1950–2007. FAO, Rome, Italy.
FAO. (2010). The State of the World Fisheries and Aquaculture 2010. FAO,
Rome, Italy.
Fernandes, A., Smith, F., Petch, R., Bradley, E., Brereton, N., Panton, S., Carr,
M. and Rose, M. (2009). Investigation into the levels of environmental con-
taminants in Scottish marine and freshwater fin fish and shellfish. Food and
Environmental Research Agency Scotland, Report no. FD 09/01.
Fisheries Research Services. (2010). Nuisance species in aquaculture: Jel-
lyfish. Available from
Fishmeal Information Network (FIN). (2001). Fishmeal for Pigs - A Feed with
a Very Healthy Future. Grain and Feed Trade Association, London, UK.
Fishmeal Information Network (FIN). (2008). Annual Review of the Feed Grade
Fish Stocks used to Produce Fishmeal and Fish Oil for the UK Market. Dossier
(2008). Grain and Feed Trade Association, London, UK.
Focken, U., Groth, A., Coloso, R. M. and Becker, K. (1998). Contribution of
natural food and supplemental feed to the gut content of Penaeus monodon
Fabricius in a semi-intensive pond system in the Philippines. Aquaculture.
Gelman, A., Drabkin, V. and Glatman, A. (2001). Evaluation of lactic acid
bacteria, isolated from lightly preserved fish products, as starter cultures for
new fish-based food products. Innovative Food Sci. Emer. Technol.1:219–226.
Gildberg, A., Johansen, A. and Bøgwald, J. (1995). Growth and survival of
Atlantic salmon (Salmo salar) fry given diets supplemented with fish protein
hydrolysate and lactic acid bacteria during a challenge trial with Aeromonas
salmonicida.Aquaculture. 138:23–34.
enez, B., Gomez-Guillen, M. C. and Montero, P. (2005b). Storage of dried
fish skins on quality characteristics of extracted gelatin. Food Hydrocolloid.
enez, B., Turnay, J., Lizarbe, M. A., Montero, P. and Gomez-Guillen, M.
C. (2005a). Use of lactic acid for extraction of fish skin gelatin. Food Hydro-
colloid. 19:941–950.
Glanville, T. D., Richard, T. L., Harmon, J. D., Reynolds, D. L., Ahn, H. K. and
Akinc, S. (2006). Environmental Impacts and Biosecurity of Composting
for Emergency Disposal of Livestock Mortalities (Final Report). Contract
no. 03-7141-08. Iowa Department of Natural Resources, Des Moines, Iowa,
Glatman, A., Drabkin, V. and Gelman, A. (2000). Using lactic acid bacteria for
developing novel fish food products. J. Sci. Food Agr. 80:375–380.
Global Agriculture Information Network (GAIN). (2007). Norway Fishery
Products Annual 2007. Report no. NO7006. United States Department of
Agriculture, Washington, D.C., USA.
Goddard, S., Al-Shagaa, G. and Ali, A. (2008). Fisheries by-catch and process-
ing waste meals as ingredients in diets for Nile tilapia, Oreochromis niloticus.
Aquaculture Res. 39:518–525.
Guerin, M., Huntley, M. E. and Olaizola, M. (2003). Haematococcus as-
taxanthin: Applications for human health and nutrition. Trend Biotechnol.
Hardy, R. W., Sealey, W. M. and Gatlin, D. M. (2005). Fisheries by-catch
and by-product meals as protein sources for Rainbow trout (Oncorhynchus
mykiss). J. World Aquacult. Soc. 36(3):393–400.
He, H.-L., Chen, X.-L., Wu, H., Sun, C.-Y., Zhang, Y.-Z. and Zhou, B.-C.
(2007). High throughput and rapid screening of marine protein hydrolysates
enriched in peptides with angiotensin-I-converting enzyme inhibitory activity
by capillary electrophoresis. Bioresource Technol. 98:3499–3505.
He, P. (2010). Anaerobic digestion: An intriguing long history in China. Wa st e
Manage. 30:549–550.
Hevrøy, E. M., Espe, M., Waagbø, R., Sandnes, K., Ruud, M. and Hemre, G.-I.
(2005). Nutrient utilization in Atlantic salmon (Salmo salar L.) fed increased
levels of fish protein hydrolysate during a period of fast growth. Aquacult.
Nutr. 11:301–313.
Hickman, D., Sims, T. J., Miles, C. A., Bailey, A. J., de Mari, M. and Koopmans,
M. (2000). Isinglass/collagen: Denaturation and functionality. J. Biotechnol.
Higgs, D. A., Balfry, S. K., Oakes, J. D., Rowshandeli, M., Skura, B. J. and
Deacon, G. (2006). Efficacy of an equal blend of canola oil and poultry fat as
an alternate dietary lipid source for Atlantic salmon (Salmo salar L.) in sea
water. I: Effects on growth performance, and whole body and fillet proximate
and lipid composition. Aquacult. Res. 37:180–191.
Hilbert, G., Lillemark, L., Balchen, S. and Schriver Hojskov, C. (1998). Reduc-
tion of organochlorine contaminants from fish oil during refining. Chemo-
sphere. 37(7):1241–1252.
Hites, R. A., Foran, J. A., Carpenter, D. O., Hamilton, M. C., Knuth, B. A. and
Schwager, S. J. (2004). Global assessment of organic contaminants in farmed
salmon. Science 303:226–229.
Holub, D. J. and Holub, B. J. (2004). Omega-3 fatty acids from fish oils and
cardiovascular disease. Molcular Cell. Biochem. 263:217–225.
Hong, S. and Secombes, C. J. (2009). Two peptides derived from trout,
IL-1fhave different stimulatory effects on immune gene expression af-
ter interperitoneal administration. Comp. Biochem. Physiol., Part B,153:
Hung, L. T., Suhenda, N., Slembrouck, J., Lazard, J. and Moreau, Y. (2010).
Comparison of dietary protein and energy utilization in three Asian cat-
fishes (Pangasius bocourti, P. hypophthalmus and P. djambal). Aquacul. Nutr.
Inter Trade Ireland. (2009). Market Report on the Composting and Anaerobic
Digestion Sectors. Inter Trade Ireland, Newry, Co. Down, UK.
International Monetary Fund. (2011). IMF primary commodity prices. Available
Je, J., Park, P., Kwon, J. and Kim, S. (2004). A novel angiotensin I converting
enzyme inhibitory peptide from Alaska pollack (Theragra chalcogramma)
frame protein hydrolysate. J. Agr. Food Chem. 52:7842–7845.
Karim, A. A. and Bhat, R. (2009). Fish gelatin: Properties, challenges, and
prospects as an alternative to mammalian gelatins. Food Hydrocolloid
Kim, S. and Mendis, E. (2006). Bioactive compounds from marine processing
byproducts—A review. Food Res. Int. 39:383–393.
Kouba, M. and Mourot, J. (2010). A review of nutritional effects on fat compo-
sition of animal products with special emphasis on n-3 polyunsaturated fatty
acids. Biochimie. XXX:1–5.
Kristinsson, H. G. and Rasco, B. (2000). Biochemical and functional properties
of Atlantic salmon (Salmo salar) muscle proteins hydrolyzed with various
alkaline proteases. J. Agr. Food Chem. 48:657–666.
Lallemont, A. (2008). A Study on Chitosan Manufacturing Plants: Case Studies
in Thailand and Ecuador. Report no. SM 07 08. Asian Institute of Technology,
Bangkok, Thailand.
Lam, P. T., Tam, M. B., Thuy, T. T. N, Gooley, G. J., Ingram, B. A., Nguyen,
H. V., Nguyen, P. T. and De Silva, S. S. (2009). Current status of farming
practices of striped catfish, Pangasianodon hypophthalmus in the Mekong
Delta, Vietnam. Aquaculture. 296:227–236.
Le Nguyen, D. K. (2007). Description of the Pangasius value chain in Vietnam.
CAS Discussion paper No 56. Centre for ASEAN Studies, Antwerp, Belgium.
Lee, C. H., Singla, A. and Lee, Y. (2001). Biomedical applications of collagen.
Int. J. Pharm. 221:1–22.
Lertsutthiwong, P., How, N., Chandrkrachang, S. and Stevens, W. (2002). Effect
of chemical treatment on the characteristics of shrimp chitosan. J. Metals
Mater. Miner. 12(1):11–18.
Li, G. Y., Fukunaga, S., Takenouchi, K. and Nakamura, F. (2005). Compara-
tive study of the physiological properties of collagen, gelatin and collagen
hydrolysate as cosmetic materials. Int. J. Cosmet. Sci. 27:101–106.
Lian, P. Z., Lee, C. M. and Park, E. (2005). Characterization of squid-processing
byproduct hydrolysate and its potential as aquaculture feed ingredient. J. Agr.
Food Chem. 53:5587–5592.
Local Government Association. (2008). LGA Landfill Tax Report: June (2008).
Local Government Association, London, UK.
Lorenz, R. T. and Cysewski, G. R. (2000). Commercial potential for Haema-
tococcusmicroalgae as a natural source of astaxanthin. Trends Biotechnol.
Downloaded by [University of Stirling Library], [Richard Newton] at 07:35 21 November 2013
adt, C. (2008). Effects of dietary acidifiers in aquaculture—A review.
Feed Technol. Update. [Feed Link Magazine (October 2008)].
Marchbank, T., Elia, G. and Playford, R. J. (2009). Intestinal protective effect
of a commercial fish protein hydrolysate preparation. Reg. Peptides 155:
endez-Acosta, H. O., Palacios-Ruiz, B, Alcaraz-Gonz´
alez, V., Gonzalez-
Alvarez, V. and Garc´
ıa-Sandoval, J. P. (2010). A robust control scheme to
improve the stability of anaerobic digestion processes. J. Process Control.
Muggli, R. (2006). Fortified foods: A way to correct low intakes of EPA and
DHA. In: Handbook of Functional Lipids. Chapter 17, pp. 389–401. Akoh,
C. C., Ed., Taylor and Francis Publishing, Boca Raton, FL.
Muyonga, J. H., Cole, C. G. B. and Duodu, K. G. (2004). Characterisation
of acid soluble collagen from skins of young and adult Nile perch (Lates
niloticus). Food Chem. 85:81–89.
Nagai, T. and Suzuki, N. (2000). Isolation of collagen from fish waste
material—Skin, bone and fins. Food Chem. 68:277–281.
Nguyen, T. T. (2010). Evaluation of Catfish (Pangasius hypophthalmus) By-
Products as Protein Sources for Pigs in the Mekong Delta of Viet Nam (Vol.
69). PhD. Thesis, Swedish University of Agricultural Sciences, Uppsala,
Nguyen, T.V., Ananth, P. A., Visvanathan,C. and Anbumozhi, V.(2009). Techno
policy aspects and socio-economic impacts of eco-industrial networking in
the fishery sector: Experiences from An Giang Province, Vietnam. J. Cleaner
Prod. 17:1272–1280.
Nguyen, D. A. T., Nguyen, A. P., Nguyen, N. L., Ta, T. K. V., Tran, T. T., Phan,
D. H., Vi, V. H. and Ha, V. C. (2009). Status and Potential for the Development
of Biofuels and Rural Renewable Energy Vietnam. Asian Development Bank,
Manila, Philippines.
Nguyen, H., Tu, B. M., Kajiwaran, N., Kunisue, T., Iwata, H., Pham, H.,
Nguyen, P., Bui, C. T. and Tanabe, S. (2006). Contamination by polybromi-
nated diphenyl ethers and persistent organochlorines in catfish and feed from
Mekong river delta, Vietnam. Environ. Toxicol. Chem. 25(10):2700–2708.
Norwegian Directorate of Fisheries. (2009). Nøkkeltall fra norsk havbruksn
æ ring. Statistics Department, Norwegian Directorate of Fisheries, Bergen,
Norwegian Seafood Export Council. (2009). Record high export of salmon
and trout. Seafood from Norway. Available from http://www.seafood±facts/View±article?key=44473.
Nwanna, L. C. (2003). Nutritional value and digestibility of fermented shrimp
head waste meal by African catfish Clarias gariepinus.Pakistan J. Nutr.
Ouraji, H., Shabanpour, B., Kenari, A. A., Shabani, A., Nezami, S., Sudagar,
M. and Faghani, S. (2009). Total lipid, fatty acid composition and lipid oxi-
dation of Indian white shrimp (Fenneropenaeus indicus) fed diets containing
different lipid sources. J. Sci. Food Agr. 89:993–997.
Pacheco, N., Garnica-Gonzalez, M., Ramirez-Hernandez, J. Y., Flores-Albino,
B., Gimeno, M., Barzana, E. and Shirai, K. (2009). Effect of temperature on
chitin and astaxanthin recoveries from shrimp waste using lactic acid bacteria.
Bioresource Technol. 100:2849–2854.
Percot, A., Viton, C. and Domard, A. (2003). Optimization of chitin extraction
from shrimp shells. Biomacromolecules. 4:12–18.
Piccolo T.(2009). Aquatic Biofuels, New Options for Bioenergy. Masters Thesis
in Business Administration, Link Campus, University of Malta.
Pichyangkura, R. (2010). Application of chitin-chitinosan from marine by prod-
ucts in Thailand. In: The FFTC-KU Joint Seminar on “Improved Utilization
of Fishery By-product as Potential Nutraceuticals and Functional Foods,
pp. 190–194. Kasetsart University, Bangkok.
Polak-Juszczak, L. (2007). Chemical characteristics of fishes new to the Polish
market. Acta Sci. Pol. Piscaria 6(2):23–32.
Prescott, C., Brown, S., Zabek, L., Staley, C. and Tolland, L. (1997). Organic
fertilization trials in conifer plantations in coastal British Columbia. In: Con-
ference Proceedings: Forest Alternative: Principles and Practice of Residuals
Use, Chapter 16, pp. 94–104. Washington University, Washington, DC.
Preto, F.,Zhang, F. and Wang,J. (2007). A study on using fish oil as an alternative
fuel for conventional combustors. Fuel. 87:2258–2268.
Raghavan, S. and Kristinsson, H. G. (2009). ACE-inhibitory activity
of tilapia protein hydrolysates. Food Chem. 117:582–588. doi:10.1016/
ırez. (2007). Salmon By-Product Proteins. Fisheries Circular No. 1027.
Fish Utilization and Marketing Service (FIIU), FAO, Rome, Italy.
Regenstein, J. M. and Zhou, P. (2007). Collagen and gelatin from marine by-
products. In: Maximising the Value of Marine By-Products, Chapter 13, pp.
279–303. Shahidi, F. Ed. Woodhead Publishing Ltd., Cambridge, UK.
RUBIN. (2009). Laksebein i fˆ
or til torsk. Biologisk Evaluering av Laksebeinmel
som Alternativ Proteinkilde i torskefˆ
or. Report no.178. RUBIN Foundation,
Trondheim, Norway.
Sachindra, N.M., Bhaskar, N. and Mahendrakar, N. S. (2006). Recovery
of carotenoids from shrimp waste in organic solvents. Waste Manag.
Sachindra, N. M. and Mahendrakar, N. S. (2005). Process optimization for
extraction of carotenoids from shrimp waste with vegetable oils. Bioresource
Technol. 96:1195–1200.
Sachs, I. (2007). The Biofuels Controversy. UNCTAD/DITC/TED/2007/12. 28
pages. United Nations Conference on Trade and Development, Geneva.
Sadowska, M. and Kolodziejska, I. (2005). Optimisation of conditions for pre-
cipitation of collagen from solution using j-carrageenan. Studies on collagen
from the skin of Baltic cod (Gadus morhua). Food Chem. 91:45.
Saito, M., Kiyose, C., Higuchi, T., Uchida, N. and Suzuki, H. (2009). Effect of
collagen hydrolysates from salmon and trout skins on the lipid profile in rats.
J. Agr. Food Chem. 57:10477–10482.
Sarabia, A. I., Gomez-Guillen, M. C. and Montero, P. (2000). The effect of
added salts on the viscoelastic properties of fish skin gelatin. Food Chem.
Seafish. (2008). Use of Waste as a Biofuel and Fertiliser in Orkney (C008).
SR609. Sea Fish Industry Authority, Edinburgh, UK.
Seafish. (2009a). 2008 Survey of the UK Seafood Processing Industry. Sea Fish
Industry Authority, Edinburgh, UK.
Seafish. (2009b). Fishmeal and Fish Oil Facts and Figures. Sea Fish Industry
Authority, Edinburgh, UK.
Seafish. (2010). Fishmeal and Fish Oil Figures. Sea Fish Industry Au-
thority, Edinburgh, UK. Available from:
Publications/SeafishFishmealandFishOilFactsand Figures (2010)09.pdf
Seoka, M., Kurata, M., Tamagawa, R., Kumar Biswas, A., Kumar Biswas,
B., Yong, A., Kim, Y.-S., Ji, S.-C., Takii, K. and Kumai, H. (2008). Dietary
supplementation of salmon roe phospholipid enhances the growth and survival
of Pacific bluefin tuna (Thunnus orientalis) larvae and juveniles. Aquaculture
SEPA. (2004). Evaluation of Fish Waste Management Techniques. Contract
Reference 230/4198. Poseidon Resource Management, Lymington, UK.
Shahidi, F. (2007). Chitin and chitosan from marine by-products. In: Maximis-
ing the Value of Marine Products. Chapter 16: pp. 340–373. Shahidi F. Ed.
Woodhead Publishing Ltd. Cambridge, UK.
Shahiri Tabarestani, H., Maghsoudlou, Y., Motamedzadegan, A. and Sadeghi
Mahoonak, A. R. (2010). Optimization of physico-chemical properties of
gelatin extracted from fish skin of Rainbow trout (Onchorhynchus mykiss).
Bioresource Technol. 101:6207–6214.
Singh, P., Benjakul, S., Maqsood, S. and Kishimura, H. (2011). Isolation and
characterisation of collagen extracted from the skin of striped catfish (Pan-
gasianodon hypophthalmus). Food Chem. 124:97–105.
e, R., Mozuraityt˙
e, R., Martinez-Alvarez, O. and Falch, E. (2009).
Functional, bioactive and antioxidative properties of hydrolysates ob-
tained from cod (Gadus morhua) backbones. Process Biochem. 44:668–
Smail D,A., Garden, A., Thompson, F., Smith, M. J., Cronj´
e, A. and Heyworth,
A. (2009). Inactivation of the Fish Pathogens Lactococcus garvieae and Infec-
tious Pancreatic Necrosis Virus in an Aerobic Composting Silo Incorporating
Shellfish. Marine Scotland Science Collaborative Report 06/09.
Smail, D. A., Huntly, P. K. and Munro, A. L. S. (1993). Fate of four fish
pathogens after exposure to fish silage containing fish farm mortalities and
conditions for the inactivation of infectious pancreatic necrosis virus. Aqua-
culture 113(3):173–181.
Downloaded by [University of Stirling Library], [Richard Newton] at 07:35 21 November 2013
Snyder, J. (2010). Feed, supplement industries maximize use of fish oil produc-
tion. Seafood Business Magazine. April 2010, 29(4):24.
Sobhi, B., Adzahan, N. M., Karim, M. S. A. and Karim, R. (2010). Physico-
chemical and sensory properties of a traditional chilli shrimp paste. J. Food
Agr. Environ. 8(1):38–40.
Sriket, P., Benjakul, S., Visessanguan, W. and Kijroongrojana, K. (2007). Com-
parative studies on chemical composition and thermal properties of black tiger
shrimp (Penaeus monodon) and white shrimp (Penaeus vannamei) meats.
Food Chem. 103:1199–1207.
SSPO. (2009). Scottish Salmon Farming Industry Research Report. Scottish
Salmon Producers’ Organisation, Perth, UK.
SSPO. (2010). Scottish Farmed Salmon Export Figures, (2008). Unpublished
Data. Scottish Salmon Producers’ Organisation. Perth, UK.
Statistics Norway. (2009). Fishery Statistics 2007. Official Statistics of Norway
D 428. Statisitcs Norway, Oslo, Norway.
Stubhaug, I., Lie, Ø. and Torstensen, B. E. (2007). Fatty acid productive value
and b-oxidation capacity in Atlantic salmon (Salmo salar L.) fed on different
lipid sources along the whole growth period. Aquaculture Nutr. 13:145–
Sudaryono, A., Tsvetnenko, E. and Evans, L. H. (1996). Digestibility stud-
ies on fisheries by-product based diets for Penaeus monodon. Aquaculture
Sun, T., Piggot, G. M. and Herwig, R. P. (2002). Lipase-Assisted concentration
of n-3 polyunsaturated fatty acids from viscera of farmed Atlantic salmon
(Salmo salar L.). J. Food Sci. 67(1):130–136.
Sun, T., Xu, Z. and Prinyawiwatkul, W. (2006). FA composition of the oil
extracted from farmed Atlantic salmon (Salmo salar L.) viscera. J. Amer. Oil
Chemists’ Soc. 83(7):615–619.
Synowiecki, J. and Al-Khateeb, N. A. A. Q. (2000). The recovery of protein hy-
drolysate during enzymatic isolation of chitin from shrimp Crangon crangon
processing discards. Food Chem. 68:147–152.
Synowiecki, J. and Al-Khateeb, N. A. A. Q. (2003). Production, properties, and
some new applications of chitin and its derivatives. Cri. Rev. Food Sci. Nutr.
Tacon, A. G. J. (2002). Thematic review of feeds and feed man-
agement practices in shrimp aquaculture. Report prepared for FAO,
World Bank, WWF, Network of Aquaculture Centres in Asia-Pacific
Tacon, A. G. J. and Metian, M. (2008). Global overview on the use of fish
meal and fish oil in industrially compounded aquafeeds: Trends and future
prospects. Aquaculture 285:146–158.
Thai Frozen Foods Association. (2009). Export Shrimp of Thailand. Thai Frozen
Foods Association, Bangkok, Thailand. Available from: http://www.thai- ex im/208.pdf.
Thistle Environmental Partnership. (2008). Strategic Waste Management and
Minimisation in Aquaculture. Scottish Aquaculture Research Forum (SARF),
Dunkeld, UK.
Thorkelsson, G. and Kristinsson, H. G. (2009). Bioactive Peptides from Marine
Sources. State of Art. Report to the NORA fund. 14-09. Matis Food Research,
Innovation and Technology, Reykjav´
ık, Iceland.
Trang, S. T. (2010). The innovative use of fishery by-products in Vietnam. In:
The FFTC-KU Joint Seminar on Improved Utilization of Fishery By-Products
as Potential Nutraceuticals and Functional Foods, pp. 76–85. Kasetsart Uni-
versity, Bangkok.
Treasurer, J. W., Hannah, F. and Cox, D. (2003). Impact of a phytoplankton
bloom on mortalities and feeding response of farmaed Atlantic salmon Salmo
salar, in West Scotland. Aquaculture. 218:103–113.
Vandanjon, L., Grignon, M., Courois, E., Bourseau, P. and Jaouen, P. (2009).
Fractionating white fish fillet hydrolysates by ultrafiltration and nanofiltration.
J. Food Eng. 95:36–44.
VASEP. (2010). Statistics of Vietnamese seafood exports 1998–2008, Chapter
2. In: Vietnam Association of Seafood Exporters and Producers. Hanoi,
VIFE (Sub-Institute for Fisheries Economics and Planning in Southern
Vietnam), (2009). Project on Development Planning for Aquaculture Produc-
tion and Consumption in the Mekong Delta up to 2015 and Strategic Planning
up to 2020. Department of Aquaculture, Ministry of Agriculture and Rural
Development. Ho Chi Minh City, Vietnam. 224 p. (In Vietnamese).
Whiteman, K. and Gatlin, D. (2005). Evaluation of fisheries by-catch and by-
product meals in diets for red drum Sciaenops ocellatus L.Aquaculture Res.
Wiggers, V.R, Wisniewski Jr., A., Madureira, L. A. S., Chivanga Barros, A.
and Meier, H. F. (2009). Biofuels from waste fish oil pyrolysis: Continuous
production in a pilot plant. Fuel. 88 (11):2135–2141.
Wisniewski Jr., A., Wiggers, V. R., Simionatto, E. L., Meier, H. F., Barros, A.
A. C. and Madureira, L. A. S. (2009). Biofuels from waste fish oil pyrolysis:
Chemical composition. Fuel. 89(3):563–568.
WWF. (2008). Aquaculture Dialogues Process Guidance Document. World
Wildlife Fund, Washington, DC, USA. Available from: http://www. what / globalmarkets /aquaculture/ WWFBinaryitem9674.
WWF. (2009). Draft Pangasius Aquaculture Dialogue Standards for the
Second Public Comment Period. World Wildlife Fund, Washington DC,
USA. Available from:
WWF. (2010). Draft Sandards for Responsible for Responsible Shrimp Aqua-
culture. World Wildlife Fund, Washington, DC, USA. Available from: what / globalmarkets / aquaculture / dialogues-
Yi, J. B., Kim, Y. T., Bae, H. J., Whiteside, W. S. and Park, H. J. (2006). Influence
of transglutaminase-induced cross-linking on properties of fish gelatin films.
J. Food Sci. 71(9):376–383.
Yunoki, S., Nagai, N., Suzuki, T. and Munekata, M. (2004). Novel biomaterial
from reinforced salmon collagen gel prepared by fibril formation and cross-
linking. J. Biosci. Bioeng. 98(1):40–47.
Yunoki, S., Suzuki, T. and Takai, M. (2003). Stabilization of low denaturation
temperature collagen from fish by physical cross-linking methods. J. Biosci.
Bioeng. 96(6):575–577.
Zampogna, F. (2009). Aquaculture Statistics - (2007). Eurostat 83/2009.
European Commission. Available from:
portal/page/portal/product details/publication?p product code=KS-SF-09-
Zhong, Y., Madhujith, T., Mahfouz, N. and Shahidi, F. (2007). Compositional
characteristics of muscle and visceral oil from steelhead trout and their ox-
idative stability. Food Chem. 104:602–608.
Zhou, P. and Regenstein, J. M. (2007). Comparison of water gel desserts from
fish skin and pork gelatins using instrumental measurements. Food Chem.
Toxicol. 72(4):196–201.
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... In order to sustainably intensify aquaculture and maintain a continuous seafood supply, without causing catastrophic ecosystem damage, there is a need to implement a more resource-efficient approach (Miller et al. 2008;Nichols et al. 2010;Tlusty and Thorsen 2017;Stevens et al. 2018) and minimize aquaculture waste (Hall et al. 2011;Castine, McKinnon, et al. 2013;Newton et al. 2014;Dauda et al. 2019;Turchini et al. 2019). Consequently, there is growing global awareness and interest in the valorization of available resources, specifically recycling of nutrients and by-products, to support a circular economy within aquaculture (Boyd et al. 2007;Arvanitoyannis and Kassaveti 2008;Alonso et al. 2010;Lopes et al. 2015;Stevens et al. 2018;de la Caba et al. 2019). ...
... In 2012, the European Commission promoted "Blue Growth", a green economy applied to maritime and coastal sectors (EC 2012). There is potential for by-products and wastewater effluents to be diverted back into aquaculture systems and account for high percentages of aquaculture production (Newton et al. 2014;Mehta et al. 2015;FAO 2018;Sm arason et al. 2019). This paper reviews the major wastewater constituents from effluents of different aquaculture systems. ...
... Extracted and isolated bioactive compounds and natural pigments such as carotenoids, collagen and protein hydrolysates from seafood by-products (Arvanitoyannis and Kassaveti 2008; Kim and Wijesekara 2010;Olsen et al. 2014;Rustad et al. 2011;Newton et al. 2014), are of interest for functional food, nutraceuticals and pharmaceutical use due to their antihypertensive, antioxidative, anticoagulant and antimicrobial properties (Ferraro et al. 2010;Kim and Wijesekara 2010). Currently these high-value components are retrieved in too small amounts for a costeffective resource recycling process, but more effective extraction methods could change this (Gildberg and Stenberg 2001;Gehring et al. 2011;Kandra et al. 2012;Olsen et al. 2014). ...
Full-text available
Aquaculture has grown rapidly to play a crucial economic and social role and meet the increasing global demand for seafood. As aquaculture intensifies, there is increasing pressure to find more sustainable practices that save resources and reduce waste. Major wastes and by-products from aquaculture were quantified across a full range of farming types. Key opportunities for wastewater treatment and by-product recovery include nutrient recycling through a combination of biofilters, bioaccumulation and multitrophic systems. To support a sustainable intensification of aquaculture, improvements in by-product harvesting, accumulation and processing methods require further investigation. Likewise, energy generated from by-products can potentially support intensified production through land-based recirculating aquaculture systems (RAS). Future challenges faced by the reuse of side streams include control of food safety and gaining consumer acceptance. Combined with increases in resource use efficiency across the aquaculture sector, from feeding methodologies to product storage, nutrient recycling can enable aquaculture to contribute sustainably toward the nutritional requirements of billions of people over the next century.
... This growing demand and limited resources push the industry to look towards recapture of nutrients whenever possible. In order to sustainably expand aquaculture and retain a constant seafood supply without damaging ecosystems, there is a need to improve resource-efficient approaches [1] and lessen aquaculture waste [2][3][4][5]. This also means we must continue to grow the feed industry, which relies on cost-effective and nutritious sources, which are limiting factors. ...
... There is a potential for rendered terrestrial animal products (e.g., poultry by-product meal, feather meal, bone and meat meal and blood meal) to be processed and used in high percentages for aquaculture production [5,11]. Hence, the application of both newly emerging and established recycling methods of animal processing have huge potential for making the industry more sustainable and significantly increasing production output. ...
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In this study, three growth trials were conducted to check the efficacy of poultry corn by-product meal, which was a combination of wet poultry processing waste and corn that was co-dried. It was relatively a new product, and its first growth trial was conducted in a laboratory (aquarium study) to evaluate the substitution of whole corn meal with poultry plus corn by-product meal (PCBM) in practical diets for channel catfish. In this trial (84 days culture period), 7 levels of PCBM (0, 5, 10, 15, 20, 25 and 30%) were evaluated in a practical diet containing 32% protein and 6% lipid. The results indicated that fish fed PCBM20 had the highest FW, WG and WG% among all the treatments, and these values were significantly higher (p < 0.05) than at baseline or with PCBM5 treatment. The second trial (fingerlings to sub-market) was conducted in 12 raceways with 4 levels of PCBM (0, 10, 20 and 30%) and 600 fish (mean initial weight 42.3 ± 5.06 g) in each raceway. After 143 days of culture, the results demonstrated that there were no significant differences (p > 0.05) between the FW, WG and WG% and the survival of the fish. To validate our results again, the third trial (sub-market to market) was conducted in 6 raceways with 2 levels of PCBM (0 and 30%). A total of 600 fish (mean initial weight 136.8 ± 6.3 g) were stocked in each raceway. The results revealed that there were no significant differences (p > 0.05) between the FW, WG and WG% and fish survival after the culture period of 133 days. In all three trials, upon termination, the hepatosomatic index (HIS), the intraperitoneal fat (IPF), and the dress-out (headed and gutted) percentages were measured for trials 2 and 3. The results showed that there were no significant differences (p > 0.05) between all these parameters except for HIS in trial 1 and IPF in trial 2 (p < 0.05). In conclusion, PCBM can be used up to 30% in the diets of channel catfish.
... This has a relatively lower quality compared to FPH, but is considered an inexpensive ingredient or feed additive (Olsen and Toppe, 2017). These by-products and derived ingredients could contribute to the human food chain indirectly through livestock or pet food ingredients, adding to the global pool of marine ingredients, especially where by-products exhibit high levels of valuable omega-3 fatty acids (Rustad et al., 2011;Newton et al., 2014). This could be more efficient than direct human consumption, especially when the flesh is technically difficult to extract and/or whole by-product is utilised, rather than just the obtainable flesh yield (Newton, 2020). ...
... Apart from higher uniformity and freshness of aquaculture by-products compared to those from most fisheries (Newton et al., 2014), feed ingredients influence the nutritional quality of the final aquaculture product (Kwasek et al., 2020;Sprague et al., 2020). Contaminant levels in farmed salmon in Europe are generally lower compared to wild salmon, which can be explained by quality control in the ingredients used (EFSA, 2012;Lundebye et al., 2017;Glencross et al., 2020). ...
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Sustainability analyses of aquaculture typically ignore the fate and value of processing by-products. The aim of this study was to characterise the nutritional content of the common processing by-products (heads, frames, trimmings, skin, and viscera) of five important finfish species farmed in Europe; Atlantic salmon (Salmo salar), European seabass (Dicentrarchus labrax), gilthead seabream (Sparus aurata), common carp (Cyprinus carpio), and turbot (Psetta maxima) to inform on best utilisation strategies. Our results indicate a substantially higher total flesh yield (64–77%) can be achieved if fully processed, compared to fillet only (30–56%). We found that heads, frames, trimmings and skin from Atlantic salmon, European seabass, gilthead seabream and turbot frames showed medium to high edible yields, medium to high lipid, and medium to high eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) content, indicating significant potential for direct use in human food. By-products which are unattractive for use in food directly but have low ash content and medium to high crude protein, lipid and EPA and DHA content, such as viscera, could be directed to animal feed. Skin showed interesting nutritional values, but has more potential in non-food applications, such as the fashion, cosmetic and pharmaceutical industries. The results indicate potential to increase the direct food, animal feed and non-food value of European aquaculture, without an increase in production volumes or the use of additional resources. The importance of changing consumer perceptions and addressing infrastructure and legislative barriers to maximise utilisation is emphasised.
... In the fisheries industry, fish filet processing produces large amounts (more than 75%) of by-products that are not edible, which are thrown away as waste or are underused in some parts of the world. The byproducts of processing marine products are rich in useful sources of biomolecules such as collagen and gelatin (Newton et al., 2014). One type of fish whose byproducts have not been widely used is tuna skin. ...
Tuna skin gelatin has the ability to form a good film, transparent color, and a good barrier against oxygen, CO2, and lipids. But the tuna skin gelatin edible film needs to be modified by adding hydrophobic materials and surfactants, to improve their physical and functional properties. The objectives were to determine the physical properties, antioxidant activity, and antimicrobial of tuna skin gelatin edible film were incorporated with ginger, clove essential oils, and surfactants. The stage 1) the extraction of gelatin from the tuna fish skin, 2) making edible films: ginger-tween edible film (GTF), ginger-soy lecithin edible film(GSF), clove-Tween® 20 edible films (CTF), and clove-soy lecithin edible film (CSF). The results showed an increase of thickness, *b values, and the highest value (*b) on GTF, but did not significantly affect *L and *a value. CTF and CSF have higher tensile strength compared to GTF, GSF, and control but not significantly different for elongation at break for all samples. Water vapor permeability was not significantly different amongst all edible films. Solubility decrease when clove essential oil was incorporated, in comparison with GTF, GSF, and control. Fourier transform infrared spectroscopy analyses spectra indicated that edible film added with clove essential oil and soy lecithin exhibited higher hydrophobicity than the control edible film. CTF showed the highest DPPH radical scavenging activities and the highest antimicrobial inhibitory activity. Therefore, clove essential oil and both surfactants could affect the physical and functional properties of resulting edible films.
... 54 For the sake of attaining sustainability in intensive aquaculture and to continue harmony in seafood supply without spawning plunging damage to the ecosystem, planning and effective implementation of resource-efficient ecosystem-based approach is the call of the day 37 to minimize aquaculture waste streaming into the open environment. 47,[55][56][57] As of now, edible fish constitutes more than 30% of the global protein consumption, of which 50% channelled through inland aquaculture and mariculture. 58 On-going production systems and generalized nutritional models resulted very often in inefficient, unsustainable results and therefore, might not support huge increase in global food demand. ...
Circular bio-economy of biogenic resources designates the plunging use of such resources, adopting a systemically formatted pathway towards sustainable economic development. Aquaculture has been perceived to play a pivotal role in supplying protein and mineral rich organic food to a growing human population. The exponential growth of aquaculture sector during the last four decades has established itself in a fundamental way to supply the global need of valuable animal protein. However, the ongoing production strategies may likely be proved unsustainable if the present level of exploitation and resource use continues. Emphasis only on augmenting productivity and yield with insufficient and/or inefficient pollution control measures, and water quality clean-ups, direct discharge of effluents in the open ambient environment from aquaculture production systems have manifested in variable degrees of pollution particularly in the open water bodies; thereby causing significant impairment of these ecosystems. The paper discusses the various techniques of bioprocessing in re-circulatory aquaculture system, aquaponics, biofloc technology, waste water aquaculture and circular enclosure culture for inland water bodies to recycle the waste generated from fisheries and aquaculture and converting the same to fish flesh, at the same time reducing the impact on environment. The study also highlights the potential attributes and benefits of circular bio-economy, discusses recent advances and updates the current status of knowledge base for future research planning towards sustainability. Rationality perspectives of the system design with regards to simplicity, energy efficiency and budget in attaining circularity emerged as pertinent factors in bio-circularity in resource use in aquaculture.
... The World Bank reported that, in 2010, the aquaculture feed industries utilized about 73% of total fishmeal globally, while 20% for pigs, 5% for poultry, and 2% for other livestock animal feed production were used (World Bank, 2013). Fishmeal is mainly produced with small pelagic species, by-catches, excess allowable catch quotas trimmings, and fish processing wastes (Cashion et al., 2017;FAO, 2019;Newton et al., 2014;Péron et al., 2010;Shepherd and Jackson, 2013). However, several recent findings have demonstrated that due to the rapid increase of plastic pollution in the marine water bodies (Hanachi et al., 2019;Lusher et al., 2017), the abundance of microplastics (MPs) in fishmeal is sharply increasing (Foekema et al., 2013;Lusher et al., 2013;Tanaka and Takada, 2016). ...
Full-text available
Plastic pollution is a global concern, leading to the abundance of macro-and microplastics (MPs) in the marine environment and subsequent accumulation in many marine organisms, particularly small pelagic and oceanic fish species. These small fishes are usually considered as the non-target catch or by-products of marine capture fisheries. However, these by-catch fishes convert into fishmeal due to their excellent nutritional value, and thereby, it used as the primary ingredient of artificial feeds for aquaculture and livestock animal production. The fishmeal and fish feed facilitates MPs' entry into the aquaculture systems when the MPs−contaminated feeds are supplied to cultured fish for regular feeding. Thus, MPs get access to interact with the elements of the culture pond ecosystem and leading to subsequent alterations in the physiological and behavioral attributes of cultured fishes. Consequently, MPs may accumulate in the edible portions of cultured fishes, which may cause severe physiological disorders in fish consumers. Thus, human exposure to MPs becomes a significant threat to global public health. Therefore, this review discussed the factors associated with MPs' introduction to the aquaculture systems via fishmeal. In addition, this article enlightened the possible consequences of MPs on the pond ecosystem, cultured fish physiology, and consumer health. We hypothesized that the growing concern among people about MPs might be impacted the demand for aquaculture goods. This study recommended taking necessary steps towards improving the MPs' screening process during fish feed production and focusing on more exclusive studies to elucidate the impacts of MPs on sustainable aquaculture production.
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Taking “blue granary” as the research object, this study focuses on the mechanism and evolution of coupling coordination relationship between green transformation and the quality of economic development, to explore the path of sustainable development. Firstly, the theoretical framework of coupling relationship between green transformation and the quality of development is constructed. Secondly, an evaluation index system is established to measure green transformation and the quality of economic development. Thirdly, the entropy approach and coupled coordination degree model are used to calculate the coordination of green transformation and the quality of economic development in different provinces in China from 2009 to 2018. The results show that: (1) Green transformation affects the quality of economic development through resource effect, social effect, and technological effect; the quality of economic development affects green transformation through new growth momentum effect, income distribution effect, scale effect, and opening up effect. (2) Both the quality of economic development and the level of green transformation continue to improve, but the growth rate of green transformation is relatively slow. (3) The overall coupled coordination relationship improves from a barely balanced stage to a favorably balanced stage, but it has not reached the ideal state of superiorly balanced, and there is significant regional heterogeneity. It will help to clarify the difference in coordinated development levels in different regions and provide a reference value for the precise implementation of eco-economic coordinated development.
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Road to Sustainable Aquaculture: This report is presented by the Sustainable Aquaculture Working Group of the Blue Food Partnership, led by the World Economic Forum’s Friends of Ocean Action platform. The goal of the Working Group is to develop a science-based global roadmap to guide the growth of sustainable aquaculture. The report assesses the current context of aquaculture including frameworks that support responsible growth, the latest in scientific knowledge, governance structures and case studies. It is prepared by ThinkAqua on behalf of the Blue Food Partnership and made possible by the generous support of the UK Government’s Blue Planet Fund. The report draws on an evidence base from peer-reviewed literature, aquaculture industry and related websites, as well as broader stakeholder consultations. Members of the Sustainable Aquaculture Working Group contributed valuable expertise to the analysis. The Working Group will build on this report to identify actions and recommendations towards a global roadmap for sustainable aquaculture.
With the rapidly increasing consumption of seafood in China, mariculture obtains a prominent position in the national economy. However, ecological security of the mariculture industry remains an important issue in China and cannot be ignored. In this paper, Lokta–Volterra model is adopted to uncover the symbiotic relationships between the economic and the ecological system over time. The results reveal that, the symbiotic relationships of mariculture industry in China can be divided into four types:mutualistic symbiosis pattern, industrial damage pattern, ecological damage pattern and mutual inhibition competition pattern. The frequency of mutualistic symbiosis and mutual inhibition competition pattern is relatively low, while the unbalanced pattern represented by ecological damage and industrial damage is dominant. When it comes to regional mariculture ecological health, Guangxi, Fujian and Tianjin are dominated by the healthy state, and Shandong and Hebei are in the sub-health state. Liaoning was in a state of high risk. For other provinces, the health states fluctuate greatly. Thus, enhancing coordination, pollution control, intensive farming, and overall planning is critical to mariculture ecological sustainability.
Atlantic salmon (Salmon salar) aquaculture has been fully developed on a large scale worldwide. Currently in the Atlantic salmon processing industry, 40–50% of the fish body ends up as by-products, which contain a variety of nutrients and are mainly processed into functional ingredients for premium pet food and animal feed. With the global increase of interest in nutritional diets and supplements, more research has been performed for the valorization of salmon by-products into value-added food products for human consumption. In the present study, an immobilized protease was used for hydrolysis of Atlantic salmon by-products to extract salmon oil. Alcalase was immobilized on chitosan-coated iron (II, III) oxide nanoparticles via glutaraldehyde crosslinking. The immobilized Alcalase was characterized using Fourier transform infrared spectroscopy and transmission electron microscope. The optimum pH and temperature range for the immobilized Alcalase were determined as 8 and 55–65 °C, respectively. The salmon oil extraction process using the immobilized Alcalase was optimized through a factorial design, and the highest oil yield of 20.55% (88.30% recovery) was obtained from 1 h of hydrolysis at 65 °C. The oil recovery using the immobilized Alcalase was comparable to the use of free Alcalase. The low levels of oxidation and hydrolysis indicated the high quality of the extracted oil, which is promising to be processed into high-value products such as nutraceuticals and pharmaceuticals. The immobilized Alcalase was collected using a magnet and reused at least three batches without a significant decrease in oil yield, indicating its potential for effective and consecutive oil extraction from salmon by-products. The present study would promote the production of value chain products from unutilized Atlantic salmon resources and achieve sustainable development of the blue economy.
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Pangasius per day for export. Pangasius is white fish, sweet, have a good smell, and do not have tiny bones. It can replace other species of white fish that are being exhausted. Pangasius is chosen as the symbol for Vietnam’s aquatic due to its high quality. Pangasius of Vietnam is as famous as other well-known aqua products such as Norway’s salmon (MOFI, 2005). Many problems, however, have been brought about by a rapid and inappropriate planned development of farming Pangasius in this delta, fluctuation price since 2003. In 2003, America accused Vietnamese enterprises of dumping catfish. Meanwhile Europe erected many technological barriers for the import of Vietnamese Pangasius (VASEP 2003). In seeking a sustainable growth for farming Pangasius in the MRD, the report will decribe the operations of actors in the Pangasius supply chain to find out the problems that are affecting the development of Pangasius aquaculture industry in the MRD.
The quality of lipid from steelhead trout viscera, a byproduct of steelhead trout industry, was evaluated and compared with that of the muscle. Steelhead trout viscera had a higher lipid content than muscle and the visceral oil differed from muscle oil in its lipid class composition. Neutral lipids, mainly triacylglycerols (TAG), comprised the major lipid class in both muscle and visceral lipid. However, as expected, muscle contained a remarkably higher level of phospholipids (PL) than viscera, and the ratio of total neutral lipids to polar lipids was lower in muscle than in viscera. Visceral and muscle lipid had similar fatty acid compositions, with the concentration of muscle polyunsaturated fatty acids (PUFA) slightly higher than that of visceral PUFA. Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) were the major n-3 PUFA present in both muscle and visceral lipid; docosapentaenoic acid (DPA) was present at about 1.61-1.76%. With respect to minor components, muscle lipid had higher a-tocopherol and total carotenoids contents than visceral lipid. Oxi-dative stability of visceral and muscle lipid, as determined by conjugated dienes (CD) and thiobarbituric acid reactive substances (TBARS), showed that visceral lipid was more stable against oxidation than muscle lipid, probably due to their different lipid profiles. Besides, carotenoids, which were present more abundantly in muscle, might have acted as prooxidants and therefore, decreased the oxi-dative stability of muscle lipid. These results suggest that steelhead trout viscera may serve as a good source of lipid and could be utilized for production of omega-3 oils.
Despite declining stocks, a major portion of the harvest of fish and marine invertebrates is discarded or used for the production of low value fish meal and fish oil. Marine by-products, though, contain valuable protein and lipid fractions as well as vitamins, minerals and other bioactive compounds which are beneficial to human health. Devising strategies for the full utilization of the catch and processing of discards for production of novel products is therefore a matter of importance for both the fishing industry and food processors. Maximising the value of marine by-products provides a complete review of the characterisation, recovery, processing and applications of marine-by products. Part one summarises the physical and chemical properties of marine proteins and lipids and assesses methods for their extraction and recovery. Part two examines the various applications of by-products in the food industry, including health-promoting ingredients such as marine oils and calcium, as well as enzymes, antioxidants, flavourings and pigments. The final part of the book discusses the utilization of marine by-products in diverse areas such as agriculture, medicine and energy production. With its distinguished editor and international team of authors, Maximising the value of marine by-products is an invaluable reference for all those involved in the valorisation of seafood by-products.
Chilli shrimp paste is a traditional Southeast Asian condiment, usually consumed uncooked as a side dish with meal or raw vegetables. Chilli shrimp paste conventionally is prepared by housewives at home or at the restaurants using toasted fermented shrimp and fresh red chillies which are ground together with a granite mortar and pestle. The physicochemical properties and consumer preference of different chilli shrimp pastes were determined. The analyses were carried out using products obtained from the hypermarkets (commercially processed), restaurants (fresh made), and a product made in the laboratory by a professional chef. The colour value, pH, total soluble solids, moisture content, salt and sucrose were investigated. The results indicated that chilli shrimp paste with approximately 70% moisture content, 27 °Brix, 4.4% salt, 10% sucrose, thick and chunky paste with lightness value (L) of 23, redness value (a) of more than 20 and yellowness value (b) of 12 was more preferred. The linear model was found to describe the correlation between panellist score and colour values. Based on the model, panellists like redness and lightness but not yellowness. The highest coefficient of (a) value shows the most effective factor in colour score by panellist was redness. The pH range of samples was from 4.02 to 6.33. The pH of the samples did not affect the preference. Chilli shrimp paste prepared in the laboratory was most preferred while the commercially processed product was least preferred. The provided information in this study will help those in the food service industry to improve their products to meet consumer demand.
Fisheries by-catch and by-product meals are portrayed as ingredients having a great potential as ingredients in aquaculture feeds. The present study was designed to evaluate the nutritional value of shrimp by-catch meal, shrimp processing waste meal, and two fish meals made from Pacific whiting (meal with and without solubles) for rainbow trout by determining apparent digestibility of these ingredients and conducting a 12-wk feeding trial with juvenile fish (average initial weight 20 g/fish). Apparent digestibility coefficients (ADCs) for protein in diets containing by-catch and processing by-products were 76% for shrimp by-catch meal, 79% for shrimp processing waste meal, 88% for Pacific whiting meal without solubles, and 92% for Pacific whiting meal with solubles. ADCs for lipid were higher than 94% for all the diets. ADCs for energy were 57% for shrimp by-catch meal, 73% for shrimp processing waste meal, 70% for Pacific whiting meal without solubles, and 73% for Pacific whiting meal with solubles. Growth performance was significantly affected by dietary protein source. Fish fed the shrimp by-catch meal diet had weight gain and feed conversion ratios similar to that of fish fed the control diet with anchovy fish meal. Fish fed diets containing shrimp processing waste and Pacific whiting meal with solubles had significantly lower weight gain and higher feed conversion ratios than the control diet. Growth was significantly lower in fish fed the Pacific whiting meal diet compared to fish fed the anchovy fish meal. The lower growth of fish fed diets containing Pacific whiting meal appeared to be a result of lower feed intake, indicating perhaps a lower palatability of this ingredient. Additional research addressing processing methods, nutritional manipulations, and palatability enhancement is needed to improve potential of some fisheries by-product meals as ingredients in the diets of rainbow trout.
The following fishes new on the Polish market were analysed: the Nile perch (Lates niloticus), oilfish (Ruvettus pretiosus, named "butter-fish" in Poland), the African catfish (Clarias gariepinus), and a pangasiid catfish (Pangasius hypophthalmus). Quantitative assays involved protein, fat, fatty acids, fat-soluble vitamins (A, E, D 3), macro-and microminerals (calcium, phosphorus, magnesium, selenium, copper), as well contaminants, such as toxic metals (arsenic, mercury, cadmium, lead) and histamine. The fishes are characterised by a varied fat content, low – in relation to Baltic fishes – levels of omega-3 fatty acids, a high content of oleic acid, and a low concentration of toxic metals and histamine.
Shell waste from shrimp Crangon crangon processing is a good source of chitin and proteins, contained on a dry basis of the offals in amounts 17.8% and 40.6%, respectively. The digestion of the shells with proteolytic enzymes allow to recovery of the chitin and nutritionally valuable protein hydrolysate. These products were prepared from the shells preliminarily demineralized with 10% HCl solution at 20°C for 30 min using commercially available Alcalase at 55°C and pH 8.5. Recovered protein hydrolysate contained, on a dry basis, 64.3% of protein (N×6.25), 6.24% lipids and 23.4% of sodium chloride and had, at pH 4.0, a minimum solubility, and 81.7% of total nitrogen in the product. The PER value of the obtained product was 2.99 as compared with that for hydrolysates from capelin (2.64) and beef longissimus dorsi muscle proteins (2.81). The charcoal decolorization of the product decreased the PER and amino acid index (EAA) values from 2.99 and 125.4 up to 2.74 and 123.2, respectively. The total amount of residual small peptides and amino acids directly attached to chitin molecules and resistant to enzymatic hydrolysis depends on degree of hydrolysis (DH) and was about 4.4% at DH value of 30%. Such purity of chitin is sufficient for many purposes.