In: Food Chemistry Research Developments ISBN 978-1-60456-262-0
Editor: Konstantinos N. Papadopoulos, pp. © 2008 Nova Science Publishers, Inc.
. A. P. Batista
, I. Sousa
, A. Raymundo
N. M. Bandarra
Instituto Nacional de Engenharia, Tecnologia e Inovação - INETI-DER - Unidade
Biomassa, Estrada do Paço do Lumiar, 1649-038 Lisboa, Portugal
Núcleo de Investigação de Engenharia Alimentar e Biotecnologia. Instituto Piaget -
ISEIT de Almada. Quinta da Arreinela de Cima, 2800-305 Almada, Portugal
DAIAT – Instituto Superior de Agronomia / Technical University of Lisbon
Tapada da Ajuda, 1349-017 Lisboa, Portugal
Departamento de Inovação Tecnológica e Valorização dos Produtos da Pesca
Instituto de Investigação das Pescas e do Mar - IPIMAR. Av. Brasília,
1449-006, Lisboa, Portugal
The implications of diet on health sustainability have assumed a major importance,
supported by considerable epidemiological evidences, and is well recognized by the
scientific community and general public, on developed countries. Microalgae are able to
enhance the nutritional content of conventional food and feed preparation and hence to
positively affect humans and animal health due to their original chemical composition,
namely high protein content, with balanced amino acids pattern, carotenoids, fatty acids,
vitamins, polysaccharides, sterols, phycobilins and other biologically active compounds,
more efficiently than traditional crops. The aim of this chapter is to review the most
important features of microalgae in animal and human nutrition, particularly in the
development of novel design-foods rich in carotenoids and polyunsaturated fatty acids
with antioxidant effect and other beneficial health properties.
L. Gouveia. A. P. Batista, I. Sousa et al. 2
Modern food industry leads to an increase of cheaper, healthier and more convenient
products. The use of natural ingredients, like polyunsaturated fatty acids (PUFA’s) and
antioxidant pigments, exhibiting high impact on functional properties is important to reduce
chronic diseases incidence, which are strongly considered of capital importance in Europe,
where aging population and welfare costs are fatal for public resources management. The
impact of natural substances introduced in the diet via "usual” foods is proved to be efficient
at long term and do not present the drawbacks of traditional therapeutic actions based on
medicines of short term impact.
Microalgae are an enormous biological resource, representing one of the most promising
sources for new products and applications (Pulz and Gross, 2004). They can be used to
enhance the nutritional value of food and animal feed, due to their well balanced chemical
composition. Moreover, they are cultivated as a source of highly valuable molecules such as
polyunsaturated fatty acids, pigments, antioxidants, pharmaceuticals and other biologically
active compounds. The application of microalgal biomass and/or metabolites is an interesting
and innovative approach for the development of healthier food products.
Microalgal biotechnology is similar to conventional agriculture, but has received quite a
lot of attention over the last decades, because they can reach substantially higher
productivities than traditional crops and can be extended into areas and climates unsuitable
for agricultural purposes (e.g. desert and seashore lands). Microalgae production is an
important natural mechanism to reduce the excess of atmospheric CO
by biofixation and
recycling of fixed C in products, ensuring a lower greenhouse effect, reducing the global
environmental heating and climate changes. Microalgae cultivation also presents less or no
seasonality, are important as feed to aquaculture and life-support systems, and can effectively
remove nutrients (or pollutants) (e.g nitrogen and phosphorus) from water. Microalgal
systems for sunlight driven environmental and production applications can clearly contribute
to sustainable development and improved management of natural resources. Lately,
microalgae have been seen with a great potential as a sustainable feedstock for biodiesel
production, in substitution for oil from vegetable crops (Campbell, 1997), and also for
hydrogen production (Dutta et al., 2005).
This chapter reviews the main applications of microalgae in feed and food products
focusing the authors’ work on this subject, for the last years.
Microalgae use by indigenous populations has occurred for centuries. However, the
cultivation of microalgae is only a few decades old (Borowitzka, 1999) and among the 30000
species that are believed to exist (Chaumont, 1993, Radmer and Parker, 1994), only a few
thousands strains are kept in collections, a few hundred are investigated for chemical content
and just a handful are cultivated in industrial quantities (Olaizola, 2003).
Some of the most biotechnologically relevant microalgae are the green algae
(Chlorophycea) Chlorella vulgaris, Haematococcus pluvialis, Dunaliella salina and the
Cyanobacteria Spirulina maxima which are already widely commercialized and used, mainly
as nutritional supplements for humans and as animal feed additives.
Microalgae in Novel Food Products 3
Chlorella vulgaris has been used as an alternative medicine in the Far East since ancient
times and it is known as a traditional food in the Orient. It is widely produced and marketed
as a food supplement in many countries, including China, Japan, Europe and the US, despite
not possessing GRAS status. Chlorella is being considered as a potential source of a wide
spectrum of nutrients (e.g. carotenoids, vitamins, minerals) being widely used in the healthy
food market as well as for animal feed and aquaculture. Chlorella is important as a health
promoting factor on many kinds of disorders such as gastric ulcers, wounds, constipation,
anemia, hypertension, diabetes infant malnutrition and neurosis (Yamaguchi, 1997). It is also
attributed a preventive action against atherosclerosis and hypercholesterolemia by glycolipids
and phospholipids, and antitumor actions by glicoproteins, peptides and nucleotides
(Yamaguchi, 1997). However the most important substance in Chlorella seems to be a beta-
1,3-glucan, which is an active immunostimulator, a free-radical scavenger and a reducer of
blood lipids (Spolaore et al., 2006).
Haematococcus pluvialis has been identified as the organism which can accumulate the
highest level of astaxanthin in nature (1.5-3.0% dry weight). This carotenoid pigment is a
potent radical scavenger and singlet oxygen quencher, with increasing amount of evidence
suggesting that surpasses the antioxidant benefits of β-carotene, vitamin C and vitamin E.
Haematococcus is currently the prime natural source of this pigment for commercial
exploitation, particularly in aquaculture salmon and trout farming (Lorenz and Cysewski,
2000). Another natural source, Phaffia rhodozyma (Xanthophyllomyces dendrorhous) yeast
requires a large amount of feed for sufficient pigmentation (Dufossé et al., 2005).
Dunaliella salina is an halotolerant microalga, naturally occurring in salted lakes, that is
able to accumulate very large amounts of β-carotene, a valuable chemical mainly used as
natural food colouring and provitamin A (retinol). The D. salina community in Pink Lake,
Victoria (Australia) was estimated to contain up to 14% of this carotenoid in their dry weight
(Aasen et al., 1969), and in culture some Dunaliella strains may also contain up to 10% and
more β-carotene, under nutrient-stressed, high salt and high light conditions (Ben-Amotz and
Avron, 1980; Oren, 2005). Apart from β-carotene Dunaliella produces another valuable
Arthrosphira (Spirulina) grows profusely in certain alkaline lakes in Mexico and Africa
and has been used as food by local populations since ancient times (Yamaguchi, 1997). It is
extensively produced around the world (3000 tons/year) and broadly used in food and feed
supplements, due of its high protein content and its excellent nutritive value, such as high γ-
linolenic acid level (Ötles and Pire, 2001, Shimamatsu, 2004). In addition, this microalga has
various possible health promoting effects: the alleviation of hyperlipidemia, suppression of
hypertension, protection against renal failure, growth promotion of intestinal Lactobacillus,
suppression of elevated serum glucose level (Spolaore et al., 2006), anticarcinogenic effect
and have hypocholesterolemic properties (Reinehr and Costa, 2006). Spirulina is also the
main source of natural phycocyanin, used as a natural food and cosmetic colouring (blue
colour extract) and as biochemical tracer in immunoassays, among other uses (Ötles and Pire,
2001, Kato 1994, Shimamatsu, 2004).
Recently, attention has been drawn on the marine microalgae Isochrysis galbana and
Diacronema vlkianum (Haptophyceae) due to their ability to produce long chain
polyunsaturated fatty acids (LC-PUFA), mainly eicosapentaenoic acid (EPA, 20:5ω3) and
L. Gouveia. A. P. Batista, I. Sousa et al. 4
also docosahexaenoic acid (DHA, 22:6ω3), that are accumulated as oil droplets in prominent
lipid bodies in the cell (Liu and Lin, 2001). These microalgae have been used as a feed
species for commercial rearing of many aquatic animals, particularly larval and juvenile
molluscs, crustacean and fish species (Fidalgo et al., 1998). For example, in a relative ranking
of microalgal diets for clam Mercenaria mercenaria, the microalga I. galbana was shown as
the most suitable source of nutritional for rapid growth (Wikfors et al., 1992), while D.
vlkianum resulted in high growth rates and low mortality for the Pacific oyster Crassostrea
gigas larvae (Ponis et al., 2006). These microalgae are also potentially promising for the food
industry as a valuable source of LC-PUFA’s, in alternative to fish oils, supplying also sterols,
tocopherols, colouring pigments and other nutraceuticals (Bandarra et al., 2003; Donato et
As with any higher plant, the chemical composition of algae is not an intrinsic constant
factor but varies over a wide range. Environmental factors, such as temperature, illumination,
pH-value, mineral contents, CO
supply, or population density, growth phase and algae
physiology, can greatly modified chemical composition. Table 1 presents indicative values of
a gross chemical composition of different algae and compared with the composition of
selected conventional foodstuffs.
Microalgae can biosynthesize, metabolize, accumulate and secrete a great diversity of
primary and secondary metabolites, many of which are valuable substances with potential
applications in the food, pharmaceutical and cosmetics industries (Yamaguchi, 1997).
One of the most obvious and arresting characteristic of the algae is their colour. In
general, each phylum has its own particular combination of pigments and an individual
colour. Aside chlorophylls, as the primary photosynthetic pigment, microalgae also form
various accessory or secondary pigments, such as phycobiliproteins and a wide range of
carotenoids. These natural pigments are able to improve the efficiency of light energy
utilization of the algae and protect them against solar radiation and related effects. Their
function as antioxidants in the plant shows interesting parallels with their potential role as
antioxidants in foods and humans (Van den Berg et al., 2000). Therefore, microalgae are
recognized as an excellent source of natural colorants and nutraceuticals and it is expected
they will surpass synthetics as well as other natural sources due to their sustainability of
production and renewable nature (Dufossé et al., 2005).
Table 1. General composition of different human sources and microalgae (% dry
matter) (adapted from Becker, 1994, Spolaore et al., 2006 and Natrah et al., 2007)
Microalgae in Novel Food Products 5
Commodity Protein Carbohydrate Lipid
*Values experimentally determined by the authors (Batista et al., 2007a).
All algae contain one or more type of chlorophyll: chlorophyll-a is the primary
photosynthetic pigment in all algae (Figure 1) and is the only chlorophyll in cyanobacteria
(blue-green algae) and rhodophyta. Like all higher plants, chlorophyta and euglenophyta
contain chlorophyll-b as well; chlorophylls -c
-d and –e can be found in several marine algae
and fresh-water diatoms. Chlorophylls amounts are usually about 0.5-1.5% of dry weight
Apart from their use as food and pharmaceutical colorants, chlorophyll derivatives can
exhibit health promoting activities. These compounds have been traditionally used in
medicine due to its wound healing and anti-inflammatory properties as well as control of
calcium oxalate crystals and internal deodorization (Ferruzi and Blakeslee, 2007). Recent
epidemiological studies from The Netherlands Cohort Study (Balder et al., 2006) has
provided evidence linking chlorophyll consumption to a decreased risk of colorectal cancer.
L. Gouveia. A. P. Batista, I. Sousa et al. 6
, chlorophyll "a"
= CHO , chlorophyll "b"
Figure 1. Chemical structures of chlorophyll a and b.
Carotenoids are naturally occurring pigments that are responsible for the different colours
of fruits, vegetables and other plants (Ben-Amotz and Fishler, 1998). Carotenoids are usually
yellow to red, isoprenoid polyene pigments derived from lycopene (Figure 2). They are
synthesized de novo by photosynthetic organisms and some other microorganisms
(Borowitzka, 1988). In animals the carotenoids ingested in the diet are accumulated and/or
metabolized by the organism, being present in meat, eggs, fish skin (trout, salmon), in the
carapace of Crustacea (shrimp, lobster, Antartic krill, crawfish), and in the subcutaneous fat,
the skin, the egg yolks, the liver, the integuments, and in the feathers of birds (poultry)
In the algae the carotenoids seem to function primarily as photoprotective agents and as
accessory light harvesting pigment, thereby protecting the photosynthetic apparatus against
photo damage (Ben-Amotz et al., 1987). They also play a role in phototropism and phototaxis
(Borowitzka, 1988). Some microalgae can undergo a carotenogenesis process, in response to
various environmental and cultural stresses (e.g. light, temperature, salts, nutrients), where the
alga stops growth and changes dramatically its carotenoid metabolism, accumulating
secondary carotenoids as an adaptation to severe environments (Bhosale, 2004).
The consumption of a diet rich in carotenoids has been epidemiologically correlated with
a lower risk for several diseases particularly those in which free radicals are thought to play a
role in initiation, such as arteriosclerosis, cataracts, age-related macular degeneration,
multiple sclerosis and cancer (Stahl and Sies, 2005; Tapiero et al., 2004). However,
unexpected results from intervention studies (ATBC, 1994; Omenn et al., 1996) with β-
carotene suggest that the threshold between the beneficial and adverse effects of some
carotenoids is low and provides a strong stimulus to further understanding the functional
effects of specific carotenoids (Van den Berg et al., 2000).
Microalgae in Novel Food Products 7
Figure 2. Chemical structures of some carotenoids. a) lycopene, b) -carotene, c) astaxhanthin, d)
lutein, e) canthaxanthin.
More than 600 known carotenoids were reported in nature and about 50 have provitamin-
A activity, which includes α-carotene, β-carotene and β-cryptoxanthin (Faure et al., 1999).
However, only very few carotenoids are used commercially: β-carotene and astaxanthin and,
of lesser importance, lutein, zeaxanthin, lycopene and bixin which are used in animal feeds,
pharmaceuticals, cosmetics and food colourings.
The main carotenoids produced by microalgae are β-carotene from Dunaliella salina and
astaxanthin from Haematococcus pluvialis.
β-carotene serves as an essential nutrient and has high demand in the market as a natural
food colouring agent, as an additive to cosmetics and also as a health food (Raja et al., 2007).
β-carotene is routinely used in soft-drinks, cheeses and butter or margarines. Is well regarded
as being safe and indeed positive health effects are also ascribed to this carotenoids due to a
pro-vitamin A activity (Baker and Gunther, 2004).
The benefits of astaxanthin are said to be numerous, and include enhancing eye health,
improving muscle strength and endurance and protecting the skin from premature ageing,
inflammation and UVA damage, is a strong coloring agent and has many functions in animals
such as growth, vision, reproduction, immune function, and regeneration (Blomhoff et al.
1992, Tsuchiya et al. 1992, Beckett and Petrovich, 1999). Some reports support the
assumption that daily ingestion of astaxanthin may protect body tissues from oxidative
damage as this might be a practical and beneficial strategy in health management. It has also
been suggested that astaxanthin has a free radical fighting capacity worth 500 times that of
vitamin E (Dufossé et al., 2005).
Besides chlorophyll and carotenoid lipophilic pigments, Cyanobacteria (blue-green
algae), Rhodophyta (red algae) and Cryptomonads algae contain phycobiliproteins, deep
colored water-soluble fluorescent pigments, which are major components of a complex
assemblage of photosynthetic light-harvesting antenna pigments - the phycobilisomes (Glazer,
1994). Phycobiliproteins are formed by a protein backbone covalently linked to tetrapyrrole
chromophoric prosthetic groups, named phycobilins (Figure 3). The main natural resources of
phycobiliproteins are the cyanobacterium Spirulina (Arthrospira) for phycocyanin (blue) and
the rhodophyte Porphyridium for phycoerythrin (red).
L. Gouveia. A. P. Batista, I. Sousa et al. 8
Figure 3. Chemical structure of a phycocyanobilin attached by thioether linkage to the apoprotein.
This group of pigments possesses a large spectrum of applications, which is evidenced by
the recent work of Sekar and Chandramohan (2007) that screened 297 patents on
phycobiliproteins from global patent databases. They are extensively used for fluorescence
applications, as highly sensitive fluorescence markers in clinical diagnosis and for labeling
antibodies used in multicolour immunofluorescence or fluorescence-activated cell-sorter
analysis (Becker, 1994).
Phycocyanin is currently used in Japan and China as a natural colouring, in food products
like chewing gums, candies, dairy products, jellies, ice creams, soft drinks (e.g. Pepsi
and also in cosmetics such as lipsticks, eyeliners and eye shadows (Sekar and Chandramohan,
2007). In a recent study, phycocyanin was considered a more versatile blue colorant than
gardenia and indigo, providing a bright blue color in jelly gum and coated soft candy, despite
its lower stability towards heat and light (Jespersen et al., 2005). A rising number of
investigations revealed several pharmacological properties attributed to phycocyanin
including, antioxidant, anti-inflammatory, neuroprotective and hepatoprotective effects
(Romay et al. 2003; Benedetti et al., 2004; Bhat and Madyastha, 2000).
Some microalgae synthesize fatty acids with particular interest (Figure 4), namely γ-
linolenic acid (GLA, 18:3ω6) (Arthrospira), arachidonic acid (AA, 20:4ω6) (Porphyridium),
eicosapentaenoic acid (EPA, 20:5ω3) (Nannochloropsis, Phaeodactylum, Nitzschia,
Isochrysis, Diacronema) and docosahexaenoic acid (DHA, 22:6ω3) (Crypthecodinium,
Schizochytrim) (Bandarra et al., 2003, Donato et al., 2003, Chini Zittelli et al., 1999, Molina
Grima et al., 2003; Spolaore et al., 2006). These long chain polyunsaturated fatty acids (more
than 18 carbons) can not be synthesized by higher plants and animals, only by microalgae
which supply whole food chains with (Pulz and Gross, 2004). Is estimated that only healthy
human adults are able to elongate 18:3ω3 to EPA in an extend lower than 5% and convert
EPA to DHA in a rate inferior to 0.05%, being inhibit in childhood and elderly life (Burdge
and Calder, 2005, Wang et al., 2006) . This statement confirms the importance of the
inclusion of these long chain fatty acids in daily diet.
Microalgae in Novel Food Products 9
Figure 4. Chemical structure of polyunsaturated fatty acids of high pharmaceutical and nutritional
Fish and fish oils are the main sources of LC-PUFA’s, still global fish stocks are
declining due to general fishing methods and over-fishing and the derived oils are sometimes
contaminated with a range of pollutants, heavy metals, toxins and typical fishy smell,
unpleasant taste and poor oxidative stability (Certik and Shimizu, 1999, Luiten et al., 2003).
The production of LC-PUFA from microalgae biotechnology is an alternative approach, and
currently microalgal DHA from Crypthecodinium and Ulkenia is commercially available by
the Martek (USA) and Nutrinova (Germany) companies (respectively), for application in
infant formulas, nutritional supplements and functional foods (Pulz and Gross, 2004,
Spolaore et al., 2006).
PUFA’s ω-3, especially DHA, are essential in infant nutrition, being important building
blocks in brain development, retinal development and ongoing visual, cognitive, as well as
important fatty acids in human breast milk (Ghys et al., 2002, Wroble et al., 2002, Arteburn
et al., 2007, Crawford, 2000). Long chain n-3 fatty acids consumption has been associated
with the regulation of eicosanoid production (prostaglandins, prostacyclins, tromboxanes and
leucotrienes) which are biologically active substances that influence various functions in cells
and tissues (e.g. inflammatory processes) being important in the prophylaxis and therapy of
chronic and degenerative diseases including reduction of blood cholesterol, protection against
cardiovascular, coronary heart diseases, atherosclerosis, diabetes, hypertension, rheumatoid
arthritis, rheumatism, skin diseases, digestive and metabolic diseases as well as cancer
(Simopoulos, 2002, Bønaa et al., 1990, Sidhu, 2003, Thies et al., 2003). Other important role
is attributed to gene expression regulation, as well as cholesterol and fasting triacylglycerol
(TAG) decreases (Calder, 2004).
The evidence of a dietary deficiency in long-chain omega3 fatty acids is firmly linked to
increased morbidity and mortality from coronary heart disease.
Tocopherols have a widespread occurrence in nature being present in both photosynthetic
(e.g. leaves) and non-photosynthetic (e.g. seedlings) tissues of higher plants and algae.
However Euglena microalga has the highest tocopherols content among the several genera of
yeast, molds and algae tested (Kusmic et al., 1999).
L. Gouveia. A. P. Batista, I. Sousa et al. 10
Studies covering a wide range of phytoplankton have suggested that the growth rates of
bivalves are related to the kind and amount of sterols present in the diet phytoplankton
(Wikfors et al., 1991). On the other hand, it has been found that many polyhydroxysterols
from marine organisms have anticancer, cytotoxic and other biological activity (Cui et al.,
2000, Tang et al., 2002, Han et al., 2003, Volkman, 2003).
The high protein content of various microalgae species is one of the main reasons to
consider them as an unconventional source of protein (Soletto et al., 2005), well illustrated by
the great interest in microalgae as single cell protein (SCP) during the 1950s. In addition, the
amino acid pattern of almost all algae compares favorably with that of other food proteins.
Since the cells are capable of synthesize all amino acids, they can provide the essential ones
to humans and animals (Guil-Guerrero et al., 2004). As other bioactive compounds
synthesized by microalgae, amino acids composition, especially the free amino acids, varies
greatly between species as well as with growth conditions and growth phase (Borowitzka,
1988). Protein or amino acids may therefore be by-products of an algal process for the
production of other fine chemicals, or with appropriate genetic enhancement, microalgae
could produce desirable amino acids in sufficiently high concentrations (Borowitzka, 1988).
Polysaccharides are widely used in the food industry primarily as gelling and/or
thickening agents. Many commercially used polysaccharides like agar, alginates and
carrageenans are extracted from macroalgae (e.g. Laminaria, Gracilaria, Macrocystis)
(Borowitzka, 1988). Nevertheless, most microalgae produce polysaccharides and some of
them could have industrial and commercial applications, considering the fast growth rates and
the possibility to control the environmental conditions regulating its growth. The most
promising microalga for commercially purposes is the unicelular red alga Porphyridium
cruentum, which produces a sulphated galactan exopolysaccharide that can replace
carrageenans in many applications. Another example is Chlamydomonas mexicana, which
releases up to 25% of its total organic production as extracellular polysaccharides and which
as found application as a soil conditioner in the USA (Borowitzka, 1988). Certain highly
sulphated algal polysaccharides also present pharmacological properties acting on the
stimulation of the human immune system (Pulz and Gross, 2004).
Microalgae biomass represents a valuable source of nearly all essential vitamins (e.g. A,
, C, E, nicotinate, biotin folic acid and pantothenic acid) and a balanced mineral
content (e.g. Na, K, Ca, Mg, Fe, Zn and trace minerals) (Becker, 2004). The high levels of
and Iron in some microalgae, like Spirulina, makes them them particularly
Microalgae in Novel Food Products 11
suitable as nutritional supplements for vegetarian individuals. The vitamin content of an alga
depends on the genotype, the stage in the growth cycle, the nutritional status of the alga, the
light intensity (photosynthetic rate). The vitamin content is therefore amenable to
manipulation by varying the culture conditions as well as by strain selection or genetic
engineering. However, vitamins cell content fluctuates with environmental factors, the
harvesting treatment and the biomass drying methods (Brown et al., 1999, Borowitzka, 1988).
Microalgae are photoautotrophic organisms that are exposed to high oxygen and radical
stresses, and consequently have developed several efficient protective systems against
reactive oxygen species and free radicals (Pulz and Gross, 2004). Hence, there is increasing
interesting in using microalgae as natural antioxidants source for cosmetics (e.g. sun-
protecting) and functional food/nutraceuticals.
Natrah et al. (2007) reported a stronger antioxidant activity exhibited by methanolic
microalgal crude extracts (from e.g. Isochrysis galbana, Chlorella vulgaris, Nannochloropsis
oculata, Tetraselmis tetrathele, Chaetoceros calcitrans) when compared with α-tocopherol,
but lower than the synthetic antioxidant BHT. However BHT and BHA synthetic
antioxidants, are questionable in terms of their safe use, since they are believed to be
carcinogenic and tumorigenic if given in high doses (Schildermann et al., 1995, Aruoma,
The microalgae represent a very large, relatively unexploited reservoir of novel
compounds, many of which are likely to show biological activity, presenting unique and
interesting structures and functions (Yamaguchi, 1997). In the last decades marine
microorganisms, particularly Cyanobacteria, have been screened for new pharmaceuticals and
antibiotics. Published data until 1996 revealed 208 cyanobacterial compounds with biological
activity while in 2001 the number of compounds screened was raised to 424, including
lipoproteins (40%), alkaloids, amides and others (Burja et al., 2001). The reported biological
activities comprise cytotoxic, antitumor, antibiotic, antimicrobial (antibacterial, antifungal,
antiprotozoa), antiviral (e.g. anti-HIV) activities as well as biomodulatory effects like
immunosuppressive and anti-inflammatory (Burja et al., 2001; Singh et al., 2003). The
cytotoxic activity, important for anticancer drugs development, is likely related to defense
strategies in the highly competitive marine environment, since usually only those organisms
lacking an immune system are prolific producers of secondary metabolites such as toxins
(Burja et al., 2001).
L. Gouveia. A. P. Batista, I. Sousa et al. 12
Several microalgae (e.g. Chlorella, Tetraselmis, Spirulina, Nannochloropsis, Nitzchia,
Navicula, Chaetoceros, Scenedesmus, Haematococcus, Crypthecodinium), macroalgae (e.g.
Laminaria, Gracilaria, Ulva, Padina, Pavonica) and fungi (Mortierella, Saccharomyces,
Phaffia, Vibrio marinus) can be used in both terrestrial and aquatic animal feed (Harel and
Feeds can be formulated by using vegetable protein sources, vegetable oil sources,
fishmeal, mineral and vitamin premixes in order to reach appropriate nutritional properties for
each animal group and promote health and welfare benefits (Harel and Clayton, 2004). Using
even very small amounts of microalgal biomass can positively affect the physiology of
animals by improved immune response, resulting in growth promotion, disease resistance,
antiviral and antibacterial action, improved gut function, probiotic colonization stimulation,
as well as by improved feed conversion, reproductive performance and weight control (Harel
and Clayton, 2004). The external appearance of the animals may also be improved, resulting
in healthy skin and a lustrous coat, for both farming animals (poultry, cows, breeding bulls)
and pets (cats, dogs, rabbits, ornamental fishes and birds) (Certik and Shimizu, 1999).
Since feed corresponds to the most important exogenous factor influencing animal health
and also the major expense in animal production, the use of alternative high quality protein
supplements replacing conventional protein sources is encouraged. Considering that animal
feed stands at the beginning of the food chain, increasing public and legislative interest is
evident, especially considering intensive breeding conditions and the recent trend to avoid
“chemicals” like antibiotics (Breithaupt, 2007). The large number of nutritional and
toxicological evaluations already conducted has demonstrated the suitability of algae biomass
as a valuable feed supplement (Becker, 1994). In fact, 30% of the current world algal
production is sold for animal feed applications (Becker, 2004).
The replacement of conventional protein in broilers rations was done by several feeding
trials and authors, using various microalgae species, namely Chlorella, Euglena, Oocystis,
Scenedesmus, Spirulina, with incorporation % depending on algae specie (usually up to 10%)
(Becker, 1994). In laying hens no differences were found in egg production rate and egg
quality (size, weight, shell thickness, solid content of the egg, albumin index, etc) and feed
conversion efficiency, between control and birds receiving 12% sewage-growth Chlorella
(Becker, 1988). Algae may serve as almost the sole source of protein in layers ration (Becker,
1988) and the yolk can have a distinct intense orange colour in layers feed the algal diet
For pigmentation purposes of broilers and/or egg yolks the diet must contain a
carotenoids source. Traditionally, dehydrated alfalfa meal and yellow corn were used
(Marusich et al., 1960, Becker, 2004). However, today, feed mills use low-cost raw material
to provide high energy diets and control the pigment content by appropriate supplementation.
Petals of Aztec marigold (Tagetes erecta), rich in lutein, have been reported to be very
effective as yolk pigmenting agent as well as synthetic canthaxanthin (Madiedo and Sunde,
1964). For laying hens feeds, canthaxanthin should not exceed 8 mg/kg since at extremely
Microalgae in Novel Food Products 13
high dosages minute crystals may be formed in the retina by a reversible deposition process
In the last decades, microorganisms such as microalgae, have been tested for
pigmentation purposes in poultry. Dunalliella bardawil can be a source of vitamin A and a
yolk enhancing agent when administrated to laying hens (Avron et al., 1952). Gouveia et al.
(1996a) reported the effect of carotenoids present in Chlorella vulgaris microalga biomass
upon pigmentation of egg yolk comparable with commercially synthetic pigments used.
Haematococcus microalga can also be used as a natural feed colourant of broiler chickens
(Kenneth, 1989, Waldenstedt et al., 2003).
Studies with chickens fed red microalga Porphyridium sp. biomass (at 5% and 10% diet
incorporation), showed a reduced blood cholesterol level and a modified fatty acid
composition in egg yolk, in spite of no differences in body weight, egg number, and egg
weight (Ginzberg et al., 2000). Chickens fed with algal biomass consumed 10% less food for
both groups, and their serum cholesterol levels were significantly lower (by 11% and 28% for
the groups fed with 5% and 10% supplement, respectively) as compared with the respective
values of the control group. Egg yolk of chickens fed with algae tended to have reduced
cholesterol levels (by 10%) and increased linoleic acid and arachidonic acid levels (by 29%
and 24%, respectively). In addition, the color of the egg yolk was darker as a result of the
higher carotenoid levels (2.4 fold higher) for chickens that fed with 5% supplement (Ginzberg
et al., 2000).
Algae are, in general, officially approved in several countries as chicken feed and do not
require new testing or approval. However, it has to be decided from case to case how
restrictive the different algae species are regarded as feed supplements (Becker, 1994). In the
European Union the Regulation (EC) No. 1831/2003 determines the use of additives in
animal nutrition and sets out rules for the authorization, marketing and labeling of feed
Aside from poultry, pigs appear to be a potential group for which algae could be used as
feed supplement. Chlorella and Scenedesmus were used for substituting soybean meal and
cotton seed meal in concentrations up to 10%, without differences in feed conversion
efficiency (Hintz et al., 1966, Hintz and Heitmann, 1967). Microalgal biomass is a feed
ingredient of good nutritional quality and suited very well for rearing pigs. It can replace
conventional proteins like soybean meal or fishmeal and no difficulties in acceptability of
algae were reported for these animals (Becker, 1994).
Spirulina has also been tested as additive in short-term and long-term experiences
(Fevrier and Seve, 1975) and all parameters studied remained identical and no differences in
reproductive capacity were observed. The authors recommended 25% of microalgal biomass
incorporation, while Yap et al. (1982) assumed 33% incorporation, without negative
L. Gouveia. A. P. Batista, I. Sousa et al. 14
It should be expected that ruminants represent the group of animals most suitable for
feeding with algae, since these animals are able to digest even unprocessed algal material
(e.g. cell walls). However a limited number of trials have been done due the large amount of
algae required to perform appropriate feeding experiments with these animal species.
Sheep’s, lambs and cattle’s shows an inability to digest efficiently the carbohydrate fraction
of the algae (Chlorella, Scenedesmus obliquus and Scenedesmus quadricauda) (Hintz et al.,
1966, Davis et al., 1975). Better digestibility was obtained with Spirulina constituting 20% of
a complete sheep diet. Calves revealed a minor difference between control and untreated
fresh Scenedesmus alga feeding animals (Calderon et al., 1976).
Microalgae feeds are currently used mainly for the culture of larvae and juvenile shell-
and finfish, as well as for raising the zooplankton required for feeding of juvenile animals
(Benemann, 1992, Chen, 2003). They are required for larval nutrition during a brief period,
either for direct consumption in the case of molluscs and peneid shrimp or indirectly as food
for the live prey, mainly rotifers, copepods and Artemia nauplii, which in turn are used for
crustaceans and fish larvae feeding (Brown et al., 1997, Duerr et al., 1998, Muller-Feuga,
2000, Xu et al., 2007).
In 1999, the production of microalgae for aquaculture reached 1000 t (62% for mollusks,
21% for shrimps and 16% for fish) for a global world aquaculture production of 43×10
plants and animals (Muller-Feuga, 2000). The most frequently used species in aquaculture are
Chlorella, Tetraselmis, Isochrysis, Pavlova, Phaeodactylum, Chaetoceros, Nannochloropsis,
Skeletonema and Thalassiosira (Yamaguchi, 1997, Borowitzka, 1997, Apt and Behrens,
1999, Muller-Feuga, 2000).
Microalgae contain essential nutrients which determine the quality, survival, growth and
resistance to disease of cultured species. These illustrate the importance of the control of
microalgal biochemical composition for the success of aquaculture feed chains, opening new
perspectives for the study of fish larval nutrition and the development of microalgae-based
feeds for aquaculture (Fábregas et al., 2001). To support a better balanced nutrition for
animal growth, it is often advised to use mixed microalgae cultures, in order to have a good
protein profile, adequate vitamin content and high polyunsaturated fatty acids, mainly EPA,
AA and DHA, recognized as essential for survival and growth during the early stages of life
of many marine animals (Volkman et al., 1989). One of the beneficial effects attributed to
adding algae is an increase in ingestion rates of food by marine fish larvae which enhance
growth and survival as well as the quality of the fry (Naas et al. 1992). In addition, the
presence of algae in rearing tanks of European sea bass larvae has been shown to increase
digestive enzyme secretion (Cahu and Zambonino-Infante 1998).
Aquatic species, such as salmonids (salmon and trout), shrimp, lobster, seabream,
goldfish and koi carp under intensive rearing conditions need a supplementation of
carotenoids pigments in their diet, to attain their characteristic muscle colour. In addition to
pigmenting effects, carotenoids, namely astaxanthin and canthaxanthin, exert benefits on
animal health and welfare, promote larval development and provide growth and performance
Microalgae in Novel Food Products 15
stimulatory effects in farmed fish and shrimp (Baker and Gunther, 2004). These effects were
proved by Torrissen (1984) during the early star-feeding of Atlantic salmon reared in fresh
water, by Christiansen et al. (1995) in Atlantic salmon parr and by Torrissen and Christiansen
(1995) that proposed a minimum of 10 mg astaxanthin or canthaxanthin per kg of diet for all
fish and crayfish; also for non-salmonid fish, authors have reported growth benefits with
carotenoids supplementation, for instance in carp and tilapia (Segner et al., 1989) and in
crustacean, such as prawn Panaeus japonicus (Chien and Jeng, 1992, Nègre-Sadargues et al.,
A positive metabolic role of carotenoids in the nutrition of larval fish and survival of
young fry was also discussed by Reitain et al. (1997), Shahidi et al. (1998), Planas and Cunha
(1999) and Lazo et al. (2000). However, the inclusion of 45 mg carotenoids in the diet (Rema
and Gouveia, 2005) besides this effectiveness on skin pigmentation, was not sufficient to
induce any differences in growth and survival of larvae and juvenile goldfish, independently
of the source (natural or synthetic).
Nevertheless, given carotenoids high costs, efforts have been deployed to evaluate the
potential of some natural pigments obtained from the red yeast Phaffia rhodozyma (Bon et
al., 1997), the marine bacteria Agrobacterium aurantiacum (Yokoyama and Miki, 1995), the
green algae Haematococcus pluvialis (Harker et al., 1996, Yuang and Chen, 2000), Chlorella
zofingiensis (Bar et al., 1995) and Chlorella vulgaris (Gouveia et al., 1996b) as dietary
carotenoid sources. Numerous reports show that carotenogenic microalgae appear as suitable
source of carotenoids in fish feeds.
Haematococcus pluvialis was assayed in rainbow trout for colouring purposes (Sommer
et al., 1991, 1992, Choubert and Heinrich, 1993) in spite of less flesh pigmentation than by
synthetic astaxanthin, due the esterified form of astaxanthin and a low availability of the
pigment inside the alga spore. However, Gomes et al. (2002) proved their efficiency on skin
pigmentation of gilthead seabream and Gouveia et al. (2003, 2005) in ornamental goldfish
and koi carp.
Chlorella vulgaris biomass proved to be efficient, comparable with synthetic astaxanthin
and canthaxanthin, for pigmentation purposes, in rainbow trout (Gouveia et al., 1996c, 1997,
1998), gilthead seabream (Gouveia et al., 2002), ornamental goldfish and koi carp (Gouveia
et al. 2003, 2005) and shrimps (Passos et al., in preparation).
Spirulina (rich in β-carotene) is usually used in aquaculture feeds up to 5-20% as a fish
and shrimp feed (Benemann, 1992) and to enhances the red and yellow patterns in carp while
leaving a brilliant white colour (Gouveia et al., 2003, 2005, Spolaore et al., 2006) and in
ornamental goldfish (Gouveia et al., 2003, 2005).
Haslea ostrearia, a diatom, induces a blue-green colour on the gills and labial palps of
oysters, which increase market’s value by 40% (Spolaore et al., 2006).
L. Gouveia. A. P. Batista, I. Sousa et al. 16
In early 1950’s microalgae were considered to be a good supplement and/or fortification
in diets for malnourished children and adults, as a single cell protein but nowadays
microalgae for human nutrition is marketed in different forms of tablets, capsules and liquids
(Spolaore et al., 2006).
Some nutritional studies were done with humans and the authors suggest that the algae
daily consumption should be restricted to about 20 g, with no harmful side effects occur, even
after a prolonged period of intake (Becker, 1988). Gross et al. (1978) performed a study
feeding algae (Scenedesmus obliquus) to children (5 g/daily) and adults (10 g/daily),
incorporated into their normal diet, during four-week test period. Hematological data, urine,
serum protein, uric acid concentration and weight changes were measured, and no changes in
the analyzed parameters were found, except a slight increase in weight, especially important
for children. The same authors also carried out a study with a slightly (group I) and seriously
(group II) malnourished infant during three weeks. The four-years-old children of group I (10
g algae/daily) showed a significant increase in weight (27 g/day) compared with the other
children of the same group who received a normal diet, and no adverse symptoms were
recorded. The second group was nourished with a diet enriched with 0.87 g algae/kg body
weight, substituting only 8% of the total protein and the daily increase in weight was about
sevenfold (in spite on a low protein contribution) and all anthropogenic parameters were
normal. The authors concluded that the significant improvement in the state of the health was
attributed not only to the algal protein but also to therapeutic factors.
However, adults are very resistant in the acceptation of novel foods with microalgae
incorporation, which was demonstrated by Feldheim (1972) and Gross and Gross (1978)
because it often affects conservative ethnic factors, including religious and socio-economic
aspects (Becker, 1994) being much easier with children’s who are more willing to accept
uncommon preparations. This was demonstrated in Mexico, where a beverage formed by
50% of a suspension of Spirulina (“green milk”) was given, without problems, as bottle feed
to babies (Jacket, 1974).
All over the world commercial production of microalgae for human nutrition is already a
reality. Numerous combinations of microalgae or mixtures with other health foods can be
found in the market in the form of tablets, powders, capsules, pastilles and liquids, as
nutritional supplements (Table 2). They can also be incorporated into food products (e.g.
pastas, biscuits, bread, snack foods, candies, yoghurts, soft drinks), providing the health-
promoting effects that are associated with microalgal biomass, probably related to a general
immune-modulating effect (Belay, 1993). In spite of some reluctance for novel foods in the
past, nowadays there is an increasing consumer demand for more natural food products,
presenting health benefits. Functional foods supplemented with microalgae biomass are
sensorily much more convenient and variable, thus combining health benefits with
attractiveness to consumers (Pulz and Gross, 2004). In some countries (Germany, France,
Japan, USA, China, Thailand), food production and distribution companies have already
started serious activities to market functional foods with microalgae and cyanobacteria (Pulz
Microalgae in Novel Food Products 17
and Gross, 2004). Food safety regulations for human consumption are the main constraint for
the biotechnological exploitation of microalgal resources, but successful cases such as the
approval (9 December 2002) of the marine diatom Odontella aurita by Innovalg (France) as a
novel food, following EC Regulation 258/97, broadens perspectives.
In the last years, our research group in Portugal aims to develop a range of novel
attractive healthy foods, prepared from microalgae biomass, rich in carotenoids and
polyunsaturated fatty acids with antioxidant effect and other beneficial properties. At the
same time toxicological studies involving all the microalgae to be incorporated are also been
conducted. Traditional foods, like mayonnaises, gelled desserts, biscuits, pasta and breakfast
cereals, largely consumed on daily basis on different European diets, are be used as vehicles
to those nutraceuticals. This strategy avoids the hassled of changing food habits; considering
that Europeans are getting older and have strong cultural motivations, being highly resistant
to food innovations. The impact of natural substances introduced in the diet via "usual” foods
is proved to be efficient at long term and do not present the drawbacks of traditional
therapeutic actions based on medicines of short term impact.
Table 2. Major microalgae commercialized for human nutrition
(Adapted from Pulz and Gross, 2004, Spolaore et al., 2006 and Hallmann, 2007)
Microalga Major Producers Products World
Hainan Simai Pharmacy Co.
Cyanotech Corp. (Hawaii, USA)
Myanmar Spirulina factory
tablets, powders, extracts
tablets, powders, beverages,
tablets, chips, pasta and
Chlorella Taiwan Chlorella
Manufacturing Co. (Taiwan)
tablets, powders, nectar,
Dunaliella salina Cognis Nutrition and Health
Blue Green Foods (USA)
powder, capsules, crystals
The viability of incorporating microalgal biomass in food systems is conditioned by the
applied processing type and intensity (e.g. thermal, mechanical), by the nature of the food
matrix (e.g. emulsion, gel, aerated dough systems) and to the interactions with other food
components (e.g. proteins, polysaccharides, lipids, sugars, salts). Besides colouring and
nutritional purposes, introducing microalgal ingredients in food systems, can also impart
significant changes in its microstructure and rheological properties (Batista et al., 2006a).
These aspects are particularly focused in our research.
L. Gouveia. A. P. Batista, I. Sousa et al. 18
The development of coloured oil-in-water emulsions using natural sources, especially
from microalgal origin, is an interesting field to investigate. The attainment of appealing and
stable colourations is an important innovation for these types of products. Due to the
antioxidant properties that most natural pigments present it is also possible to improve the
resistance to oil oxidation, which is particularly advantageous in high fat products like
The addition of natural pigments, typically present in microalgae, to oil-in-water (o/w)
emulsions was studied by Batista et al. (2006a, 2006b). The emulsions were prepared with
3% (w/w) pea protein isolate and 65% (w/w) vegetable oil, according to previous studies that
successfully replaced egg yolk protein by leguminous proteins in o/w emulsions (Raymundo
et al., 2002). Commercial lutein oil dispersion (FloraGlo
, Kemin, USA) and phycocyanin
extracted from Sprirulina (Arthrospira) maxima laboratory cultures (INETI, Portugal) (Reis
et al., 1998) were used, at concentrations ranging from 0.25% to 1.25% (w/w). Emulsions
containing both pigments, in different proportions (total pigment concentration of 0.5% w/w)
were also prepared. Regarding carotenoids lipophilic character, lutein was added to the
emulsions dispersed oil phase while phycocyanin, being an hydrophilic proteinaceous
pigment, was added to the continuous aqueous phase, prior to the emulsification process.
Lutein (yellow) and Phycocyanin (blue) imparted appealing and innovative colourations
to food emulsions, as can be observed in Figure 5. However, the addition of these pigments
had significant implications on the emulsions structural and rheological properties. The
effects were markedly different for the two pigments used. Their distribution between the
continuous (aqueous) and dispersed (oil) phase and its interactions with the emulsifier
molecules at the interface seems to be of major importance (Batista et al., 2006b).
a) b) c) d)
Figure 5. Oil-in-water (o/w) pea protein-stabilized emulsions, a) without pigment addition (control), b)
with 0.50% (w/w) lutein, c) with 0.50% (w/w) phycocyanin, d) with both pigments in equal proportion
50L:50P (0.50% total piment).
The addition of lutein had a negative impact on the emulsion microstructure and
rheological characteristics (Figure 6), although there were no significant differences between
samples with different lutein concentrations. Adding lutein to the oil fraction could have
modified the nature of the emulsions’ dispersed phase, namely the strength of the attractive
interactions between molecules and the effectiveness of their packing in the condensed phase
(McClemments, 1999). Recent studies (Granger et al., 2003, Rampon et al., 2004) have
suggested that not only the surfactant molecules, i.e. emulsifiers and proteins, but also the fat
Microalgae in Novel Food Products 19
used in the emulsions formulation participates in the development of the interface
characteristics and rheological properties. Lutein molecules are mainly lipophylic molecules
but present polar hydroxyl groups in both ends of the conjugated polyisoprenoid chain, so it is
possible to interact with hydrophobic domains of the pea protein emulsifier, creating weaker
and disordered layers. Santipanichwong and Suphantarika (2007) also reported emulsion
destabilization by the addition of lutein in reduced-fat mayonnaises with spent brewers’ yeast
as fat replacer.
On the other hand, phycocianin addition resulted in a significant improvement of the
emulsions rheological properties (Figure 6) which increased linearly with phycocyanin
concentration (Batista et al., 2006a). The presence of phycocyanin protein molecules may
have contributed to a marked increase in the viscosity of the aqueous continuous phase, thus
retarding the oil droplet association movements and consequently enhancing emulsion
stability. It is also possible that phycocyanin protein molecules interact in the interfacial
protein adsorbed layer at the surface of oil droplets, reinforcing in this case the pea protein
emulsifier film and imparting stability to emulsions. In fact, previous studies (Chronakis et
al., 2000) have demonstrated that a protein isolate from blue-green algae (Spirulina platensis
strain Pacifica), containing phycocyanin, was capable of reducing the interfacial tension at the
aqueous/air interface at relatively lower bulk concentrations compared to common food
Figure 6. Mechanical spectra of o/w emulsions without pigment addition (control), with 0. 50% lutein,
0.50% phycocyanin, and with both pigments in equal proportion 50L:50P (0.50% total pigment).
When using combinations of both pigments, an increase of the rheological and
parameters with phycocyanin proportion was apparent, and a synergetic effect was observed
when using small amounts (< 50% proportion) of lutein.
L. Gouveia. A. P. Batista, I. Sousa et al. 20
The use of the microalgae Haematococcus pluvialis (carotenogenic) and Chlorella
vulgaris (before and after carotenogenesis) to colour oil-in-water pea protein-stabilized
emulsions was also investigated by the authors (Gouveia et al., 2006), obtaining a wide range
of attractive and stable tonalities (Figure 7). These microalgae were cultivated in the Biomass
Unit of the Department of Renewable Energies from INETI (Portugal).
Figure 7. Oil-in-water (o/w) pea protein-stabilized emulsion with 0.25%, 0.50% and 0.75% (w/w)
(from left to right) of Haematococcus pluvialis (top) and Chlorella vulgaris biomass (carotenogenic)
The colour stability of the emulsions was evaluated, through the evolution of the L*a*b*
parameters (CIELAB system) along six weeks. The primary and secondary oxidation
products of the emulsions were also determined, and an enhanced resistance to oxidation was
evidenced by emulsions containing microalgae (Gouveia et al., 2006). The incorporation of
Haematococcus pluvialis provided higher oxidation stability over time, in comparison with
Chlorella vulgaris. It should be considered that during carotenogenesis Haematococcus
pluvialis accumulates mainly astaxanthin while canthaxanthin is the dominant carotenoid in
Chlorella vulgaris. The higher oxidation stability of astaxanthin as already been reported, and
is related to the fact that antioxidant effectiveness of carotenoids increases as the number of
the conjugated double bounds of carotenoids increased (Yen and Chen, 1995). However,
microalgal biomass may be considered as multi-component antioxidant systems, which are
generally more effective due to synergistic or additive interactions between the different
The addition of microalgal components improved the emulsion textural parameters which
should be related with a higher stability level. It can also be observed that 0.75% (w/w)
biomass seems to be an optimal concentration level, since the three emulsions presented
similar firmness values (2.3-2.5 N) (Figure 8). At higher concentrations the emulsions became
excessively firm, which could be related to an increase on the viscosity of the aqueous phase.
Microalgae in Novel Food Products 21
y = 2.9252 x + 0.2449
R2 = 0.9739
y = 2. 2137x + 0.7281
R2 = 0.75 51
y = 1.7851 x + 1.0379
R2 = 0.9088
0.0 0.5 1.0 1.5 2.0 2.5
% Microalgal biomass (w/w)
Chlorella g reen
Chlorella o rang e
Figure 8. Firmness values of oil-in-water pea protein-stabilized food emulsions coloured with different
concentrations of Haematococcus pluvialis, Chlorella vulgaris green and Chlorella vulgaris orange
Figure 9. Mechanical spectra of pea protein-stabilized o/w emulsions with and without 2% w/w
Chlorella green and orange biomass, at different oil contents.
The capacity of the Chlorella vulgaris biomass as a fat mimetic, and its emulsifier ability,
has also been studied (Raymundo et al., 2005). Pea protein emulsions with Chlorella vulgaris
addition (both green and orange - carotenogenic) were prepared at different protein (2-5%
w/w) and oil (50-65% w/w) contents, characterized in terms of rheological behaviour. It was
observed that emulsions with 55% oil and 2% microalga were more structured than the
L. Gouveia. A. P. Batista, I. Sousa et al. 22
emulsions with 65% oil and no microalgal biomass addition (Figure 9). This behaviour can be
explained by the increase of the viscosity of the continuous phase of the emulsion, by the
microalgal material. This result supports the potential use of using microalgae material to act
as a fat mimetic, besides the possible advantages as colouring and antioxidant agent. The
development of the emulsion structure did not occur when microalgal biomass fully replaced
the vegetable protein as an emulsifier, and phase separation was instantaneous.
Short dough cookies and biscuits are widely consumed food products, appreciated for
their taste, versatility, convenience, conservation, texture and appearance. The use of natural
ingredients, exhibiting functional properties and providing specific health benefits beyond
traditional nutrients, is a very attractive way to design new food products, with an important
market niche presently exhibiting pronounced growth.
A study was undertaken to determine the effects of adding Chlorella vulgaris biomass as
a colouring ingredient in traditional butter biscuits (Gouveia et al., 2007a). The cookies were
manufactured at a pilot scale, according to an optimized formulations from previous studies
(Piteira et al., 2004), and stored for three months at room temperature, protected from light
Chlorella vulgaris biscuits presented an accentuated green tonality (Figure 10), which
increased with the amount of added biomass. In general, colour parameters (CIELAB system)
remained very stable along the storage period. However, it seems not necessarily to use
biomass concentrations above 1% (w/w), since the green tonality (-a*) differences are no
longer significant (p<0.05), and higher algal concentrations are related with some colour
variations along time (Figure 11a).
Figure 10. Biscuits with Chlorella vulgaris biomass, a) at various concentration levels (0.0-3.0%), b)
and in comparison with Haematococcus pluvialis (pink) and Chlorella vulgaris (orange) carotenogenic
The texture profile of the biscuits was also evaluated, and a significant increase of their
firmness was evidenced with an increase of added microalgal biomass (Figure 11b). These
Microalgae in Novel Food Products 23
results evidence the positive effect of the alga in the biscuit structure, reinforcing the short
dough system. Biscuit are considered solid emulsions of sucrose, lipids and non-gelatinized
starch (Hoseney et al., 1988), being this morphology is responsible for the biscuits structure
and texture. The main factor affecting these properties is the moisture content and water
mobility, which are highly affected by the interaction with hydroxyl groups present in the
matrix (Hoseney et al., 1988). The replacement of a small amount of flour by microalgae
biomass, resulted in the inclusion of a complex biomaterial, rich in different proteins and
polysaccharides. These molecules have an important role on the water absorption process,
which promote the increase of biscuits firmness, resulting in more compact structures.
0.0% 0.5% 1.0% 2.0% 3.0%
% Chlorella vulgaris (w/w)
0.0% 0.5% 1.0% 2.0% 3.0%
% Chlorella vulgaris (w/w)
Figure 11. Green chromaticity a* (a) and firmness values (b) of biscuits with different concentrations of
Chlorella vulgaris biomass, after one week and three months storage.
L. Gouveia. A. P. Batista, I. Sousa et al. 24
A similar study was performed, this time using Isochrysis galbana biomass (Gouveia et
al., 2007b), that was cultivated in the Department of Aquaculture of IPIMAR (Portugal). An
enhancement of the biscuits texture properties and high stability of colour and texture along
three months storage was observed, as previously reported for Chlorella biscuits (Gouveia et
al., 2007a). The biscuits presented quite different tonalities, turning from green to a brownish
and duller tonality when increasing the biomass concentration from 1.0% to 3.0% (Figure 12).
Figure 12. Biscuits with different incorporation levels (0.0%, 1.0%, 3.0%) of Isochrysis galbana
The main interest in using Isochrysis galbana biomass is due to its high levels of long
chain omega-3 polyunsaturated fatty acids, especially EPA and DHA (Bandarra et al., 2003).
The biscuits fatty acids profile is clearly related to butter (Özkanli and Kaya, 2007), with
predominance of saturated (~60%) and monounsaturated fatty acids (~30%), mainly palmitic
acid (30-40%) and oleic acid (18:1ω9) (20-25%), respectively. Polyunsaturated fatty acids
corresponded to 6-9% (4-5% linoleic acid; 18:2ω6), the highest levels being for 3% Ig
biscuits (55% linoleic acid, 15% EPA, 6% -linolenic acid and 3% DHA).
0% 1% 3%
Figure 13. Omega-3 polyunsaturated fatty acids, of biscuits with 0%, 1% and 3% Isochrysis galbana
Microalgae in Novel Food Products 25
In spite of the drastic thermal processing (high temperatures) during biscuits
manufacturing, the addition of microalgal biomass leads to the presence of 3 fatty acids
(absent in control biscuits) which remain stable along storage time (Figure 13). The thermal
resistance of fatty acids should be due to its presence in an encapsulated form, inside the
microalga. Ig biscuits presented LC-PUFA’s-ω3 levels (EPA+ DHA) of 100 mg/100g and 30
mg/100g biscuit, for 1% and 3% microalgal biomass incorporation, respectively (Figure 13).
These values reflect an important source of PUFA-3 with a moderate biscuit consumption,
as the recommendations for dietary intake in healthy adults is 500 mg/day (ISSFAL, 2004).
Most recently, our group is studying the incorporation microalgal biomass in food gelled
products, based on protein and polysaccharide mixed biopolymer systems. Gelled vegetable
desserts, alternative to dairy desserts, with pea protein isolate (4% w/w), κ-carrageenan
(0.15%) and starch (2.5%), optimized in previous studies (Nunes et al., 2003, 2006) were
used as model systems. The gels were prepared with different microalgae - Spirulina
(Arthrosphira) maxima, Chlorella vulgaris (green and orange, after carotenogenesis),
Haematococcus pluvialis (red, carotenogenic) and Diacronema vlkianum – were evaluated in
terms of colour and texture and compared with gels prepared with commercial pigments –
phycocyanin, astaxanthin, β-carotene, canthaxanthin and lutein. The microalgae gels imparted
less intense tonalities (Figure 14) and texture modifications, compared to the pigment
The pea protein/κ-carrageenan/starch mixed gel systems with 0.75% (w/w) microalgal
biomass addition were characterized in terms of rheological behaviour, including monitoring
of the viscoelastic functions (G’, G”) during gelification (cooling process) and maturation
kinetics (Batista et al., 2007b).
Figure 14. Gelled vegetable desserts with incorporation of microalgae biomass (a) and commercial
The incorporation of these biomaterials seemed to be beneficial, especially for
Haematococcus pluvialis which promoted a structural reinforcement expressed by improved
rheological properties (Figure 15). This may be related to its significantly higher fat content
L. Gouveia. A. P. Batista, I. Sousa et al. 26
(40.7%) in relation to other microalgae. The influence of fat content on gelling behaviour has
been studied in milk gelled systems (Houzé et al., 2005, Vélez-Ruiz et al., 2005) being
concluded that using high fat milk rather than skim milk results in stronger gels, which is
usually attributed to fat droplets acting as active filler particles embedded in the protein
However, the addition of Spirulina promoted a drastic reduction on the gels rheological
parameters (Figure 15), which should be related with a thermodynamic incompatibility
between the microalgal protein and other components of the mixed gelled system. In fact,
Chronakis (2001) reported that proteins isolated from Spirulina are quite intricate
biomaterials, likely to be protein and/or protein-pigment (phycocyanin) complexes rather than
individual protein molecules. Therefore, Spirulina denaturation and gel formation is a
complex phenomenon per se, which can probably interfere with the gelling process of the
biopolymers present in the mixed gel system.
Further research is required in order to better understand the gelation mechanism of these
microalgae and the specific interactions with each biopolymer present in the complex mixed
gel system, as well as the influence of processing conditions (e.g. temperature, heating and
Figure 15. Maturation kinetic curves (a) and mechanical spectra (b), at 5ºC, of pea protein/κ-
carrageenan/starch gels () with 0.75% (w/w) Haematococcus pluvialis (
) and Spirulina maxima ()
biomass. G’ (filled symbol), G” (open symbol).
The combination of the exceptional nutritional value of microalgae with colouring and
therapeutical properties, associated with an increase demand of natural products, make
microalgae worth exploring for utilization in the future in feed, food, cosmetic and
pharmaceutical industries, with recognized advantages comparing with the traditional
In the actual scenario with multiple pharmacological treatments, many believe that simple
dietary interventions or nutritional supplements may be more natural, acceptable and feasible
method of providing benefits.
Microalgae in Novel Food Products 27
Choose of the right food to eat in an early stage of life associated with a healthy lifestyle
can have important benefits in future life. A healthy diet based on microalgae novel food
products can have important benefits for all age groups.
The great results obtained by the authors in the preparation of common food products
with microalgae incorporation providing attractive and healthier food with enormous potential
as a functional food ingredient.
In the near future, the authors’ intent to continue the development of healthier food
products, preparing other widespread food product, such as pasta, salt crackers, extruded
products with the incorporation of microalgal biomass, as a vehicle of functional ingredients,
namely pigments, antioxidants and PUFA’s.
This work is part of a research project “Pigments, antioxidants and PUFA’s in
microalgae based food products – functional implications” (PTDC/AGR-ALI/65926/2006)
sponsored by the Portuguese Foundation for the Science and Technology (“Fundação para a
Ciência e a Tecnologia” - FCT). A.P. Batista acknowledges the PhD research grant from
Aasen, A.J., Eimhjellen, K.E., and Liaaen-Jensen, S. (1969). An extreme source of β-
carotene. Acta Chemica Scandinavica, 23, 2544-2545.!
Apt, K.E., and Behrens, P.W. (1999). Commercial developments in microalgal
biotechnology. Journal of Phycology, 35, 215-226.
Arteburn, L.A., Oken, H.A., Hoffman, J.P., Bailey-Hall, E., Cheng, G., Rom, D., Hamersley,
J., and McCarthy, D. Bioequivalence of docosahexaenoic acid from different algal oils in
capsules and in DHA-fortified food. Lipids, In press (DOI: 10.1007/s11745-007-3098-5).
Aruoma, O.I. (2003). Methodological considerations for characterizing potential antioxidant
actions of bioactive components in plant foods. Mutation Research, 523, 9-20.
ATBC Cancer Prevention Study Group (1994). The effect of vitamin E and beta carotene on
the incidence of lung cancer and other cancers in male smokers. The New England
Journal of Medicine, 330, 1029-1035.
Avron, M., Ben-Amotz, A., and Edelstein, S. (1952). Use of Dunalliella bardawil as a source
of vitamin A and a yolk-color enhancing agent. Commonwealth of Australia Patent Act
Bandarra, N.M., Pereira, P.A., Batista, I., and Vilela, M.H. (2003). Fatty acids, sterols and –
tocopherol in Isochrysis galbana. Journal of Food Lipids, 18, 25-34.
Baker, R., and Gunther, C. (2004). The role of carotenoids in consumer choice and the likely
benefits from their inclusion into products for human consumption. Trends in Food
Science and Technology, 15, 484-488.
L. Gouveia. A. P. Batista, I. Sousa et al. 28
Balder, HF, Vogel, J., Jansen, M.C., Weijenberg, M.P., van den Brandt, P.A., Westenbrink,
S., van der Meer, R., and Goldbohm, R.A. (2006). Heme and chlorophyll intake and risk
of colorectal cancer in the Netherlands cohort study. Cancer Epidemiology Biomarkers
and Prevention, 15,717-725.
Bar, E., Rise, M., Vishkautsan, M., and Arad, S. (1995). Pigment and structural changes in
Chlorella zofingiensis upon light and nitrogen stress. Journal of Plant Physiology, 146,
Batista, A.P., Raymundo, A., Sousa, I., and Empis, J. (2006a). Rheological characterization
of coloured oil-in-water food emulsions with lutein and phycocyanin added to the oil and
aqueous phases. Food Hydrocolloids, 20, 44-52.
Batista, A.P., Raymundo, A., Sousa, I., Empis, J., and Franco, J.M. (2006b). Colored food
emulsions – implications of pigment addition on the rheological behaviour and
microstructure. Food Biophysics, 1, 216-227.
Batista, A.P., Bandarra, N., Raymundo, A., and Gouveia, L. (2007a). Microalgae biomass – a
potential ingredient for the food industry. EFFoST/EHED Joint Conference. Lisbon,
Batista, A.P., Gouveia, L., Nunes, M.C., Franco, J.M., and Raymundo, A. (2007b).
Microalgae biomass as a novel functional ingredient in mixed gel systems. In Gums and
Stabilisers for the Food Industry – 14
Edition. Eds. P.A. Williams, G.O. Phillips. Royal
Society of Chemistry.
Becker, E.W. (1988). Micro-algae for human and animal consumption. In M.M. Borowitzka,
and L.J. Borowitzka (Eds), Micro-algal biotechnology (pp. 222-256). Cambridge
Becker, E.W. (1994). Microalgae: biotechnology and microbiology. Cambridge University
Becker, E.W. (2004). Microalgae in human and animal nutrition. In A. Richmond (Ed),
Handbook of microalgal culture (pp. 312-351). Oxford: Blackwell.
Beckett, B.R., and Petkovich, M. (1999). Evolutionary conservation in retinoid signalling and
metabolism. American Zoology, 39, 783-795.
Belay, A. (1993). Current knowledge on potential health benefits of Spirulina platensis.
Journal of Applied Phycology, 5, 235-240.
Ben-Amotz, A., and Avron, M. (1980). Glicerol, β-carotene and dry algal meal production by
commercial cultivation of Dunaliella. In G. Shelef, and C.J. Soeder (Eds), Algae Biomass
(pp. 603-610). Amsterdam: Elsevier/North Holland Biomedical Press.
Ben-Amotz, A., Gressel, J., and Avron, M. (1987). Massive accumulation of phytoene
induced by norflurazon in Dunaliella bardawil (Chlorophyceae) prevents recovery from
photoinhibition. Journal of Phycology, 23, 176-181.
Ben-Amotz, A., and Fishler, R. (1998). Analysis of carotenoids with emphasis on 9-cis-β-
carotene in vegetables and fruits commonly consumed in Israel. Food Chemistry, 62,
Benedetti, S., Benvenuti, F., Pagliarani, S., Francogli, S., Scoglio, S., and Canestrari, F.
(2004). Antioxidant properties of a novel phycocyanin extract from the blue-green alga
Aphanizomenon flos-aquae. Life Sciences, 55, 2353-2362.
Microalgae in Novel Food Products 29
Benemann, J.R. (1992). Microalgae aquaculture feeds. Journal of Applied Phycology, 4, 233-
Bhat, V.B., and Madyastha, K.M. (2000). C-Phycocyanin: a potent peroxyl radical scavenger
in vivo and in vitro. Biochemical and Biophysical Research Communications, 275, 20-
Bhosale, P. (2004). Environmental and cultural stimulants in the production of carotenoids
from microorganisms. Applied Microbiology and Biotechnology, 63, 351-361.
Blomhoff, R., Green, M.H., and Norum, K.R. (1992). Vitamin A: physiological and
biochemical processing. Annual Reviews in Nutrition, 12, 37-57.
Bon, J.A., Leathers, T.D., and Jayaswal, R.K. (1997). Isolation of astaxanthin-overproducing
mutants of Phaffia rhodozyma. Biotechnology Letters, 19, 109-112.
Bønaa, K.H., Bjerve, K.S., Straume, B., Gram, I.T., and Thelle, D. (1990) Effect of
eicosapentaenoic and docosahexaenoic acids on blood pressure in hypertension: a
population-based intervention trial from the Tromsø study. New England Journal of
Medicine, 322, 795-801.
Borowitzka, M.A. (1988). Vitamins and fine chemicals from micro-algae. In M.A.
Borowitzka, and L.J. Borowitzka (Eds), Micro-algal biotechnology (pp. 153-196).
Cambridge, UK: Cambridge University Press.
Borowitzka, M.A. (1997). Microalgae for aquaculture: opportunities and constraints. Journal
of applied phycology, 9, 393-401.
Borowitzka, M.A. (1999). Commercial production of microalgae: ponds, tanks, tubes and
fermenters. Journal of Biotechnology, 70, 313-321.
Breithaupt, D.E. (2007). Modern application of xanthophylls in animal feeding - a review.
Trends in Food Science and Technology, 18, 501-506.
Brown, M.R., Jeffrey, S.W., Volkman, J.K., and Dunstan, G.A. (1997). Nutritional properties
of microalgae for mariculture. Aquaculture, 151, 315-331.
Brown, M.R., Mular, M., Miller, I., Farmer, C., and Trenerry, C. (1999). The vitamin content
of microalgae used in aquaculture. Journal of Applied Phycology, 11, 247-255.
Burdge, G.C., and Calder, P.C. (2005). alfa-Linolenic acid metabolism in adult humans:the
effects of gender and age on conversion to longer-chain polyunsaturated fatty acids.
European Journal of Lipid Science and Technology, 107, 426–439.
Burja, A.M., Banaigs, B., Abou-Mansour, E., Burgess, J.G., Wright, P.C. (2001). Marine
cyanobacteria - a prolific source of natural products. Tetrahedron, 57, 9347-9377.
Cahu, C.L., and Zambonino-Infante, J.L. (1998). Algal addition in sea bass (Dicentrarchus
labrax) larvae rearing: effect on digestive enzymes. Aquaculture, 161, 479-489.
Calder, P.C. (2004). Review - n–3 Fatty acids and cardiovascular disease: evidence explained
and mechanisms explored. Clinical Science, 107, 1–11.
Calderon, C.J.F., Merino, Z.H., and Barragán, M.D. (1976). Valor alimentico del alga
espirulina (Spirulina geitleri) para ruminants. Tecnica Pecuaria en Mexico, 31, 42-46.
Campbell, C.J. (1997). The Coming Oil Crisis. Essex, England: Multi-Science Publishing
Company and Petroconsultants.
Certik, M., and Shimizu, S. (1999). Biosíntesis and regulation of microbial polyunsaturated
fatty acid production. Journal of Biosciences and Bioengineering, 87, 1-14.
L. Gouveia. A. P. Batista, I. Sousa et al. 30
Chaumont, D. (1993). Biotechnology of algal biomass production: a review of systems for
outdoor mass culture. Journal of Applied Phycology, 5, 593-604.
Chen, Y.-C. (2003). Immobilized Isochrysis galbana (Haptophyta) for long-term storage and
applications for feed and water quality control in clam (Meretrix lusoria) cultures.
Journal of Applied Phycology, 15, 439-444.
Chien, Y.H., and Jeng, S.C. (1992). Pigmentation of kuruma prawn, Panaeus japonicus Bate,
by various pigment sources and levels and feeding regimes. Aquaculture, 102, 333-346.
Chini Zittelli, G., Lavista, F., Bastianini, A., Rodolfi, L., Vincenzini, M., and Tredici, M.R.
(1999). Production of eicosapentaenoic acid by Nannochloropsis sp. cultures in outdoor
tubular photobioreactors. Journal of Biotechnology, 70, 299-312.
Choubert, G., and Heinrich, O. (1993) Carotenoid-pigments of the green-alga
Haematococcus pluvialis – assay on rainbow trout, Oncorhynchus mykiss, pigmentation
in comparison with synthetic astaxanthin and canthaxanthin. Aquaculture, 112, 217-226.
Christiansen, R., Glette, J., Lie, O., Torrissen, O.J., and Waagbo, R. (1995). Antioxidant
status and immunity in Atlantic salmon, Salmo salar, fed semi-purified diets with and
without astaxanthin supplementation. Journal of Fish Diseases, 18, 317-328.
Chronakis, I.S., Galatanu, A.N., Nylander, T., and Lindman, B. (2000). The behaviour of
protein preparations from blue-green algae (Spirulina platensis strain Pacifica) at the
air/water interface. Colloids and Surfaces A: Physicochemical and Engineering Aspects,
Chronakis, I.S. (2001). Gelation of edible blue-green algae protein isolate (Spirulina platensis
strain Pacifica): thermal transitions, rheological properties, and molecular forces
involved. Journal of Agricultural and Food Chemistry, 49, 888-898.
Clark, D.C., Wilde, P.J., Wilson, D.R., and Wustneck, R. (1992). The interaction of sucrose
esters with β-lactoglobulin and α-casein from bovine milk. Food Hydrocolloids, 6, 173-
Crawford, M. (2000). Placental delivery of arachidonic acid and docosahexaenoic acids:
implication of the lipid nutrition of preterm infants. American Journal of Clinical
Nutrition, 71, 275S-284S.
Cui, J.G., Wang, Y., Lin, G.W., and Zeng, L.M. (2000). Polyhydroxylated sterols with
biological activities in marine organism. Natural Products Research Developments, 12,
Davis, I.F., Sharkey, M.J., and Williams, D. (1975). Utilization of sewage algae in association
with paper in diets of sheep. Agriculture and Environment, 2, 333-338.
Donato, M., Vilela, M.H., and Bandarra, N.M. (2003). Fatty acids, sterols, α-tocopherol and
total carotenoids composition of Diacronema vlkianum. Journal of Food Lipids, 10, 267-
Duerr, E.O., Molnar, A., and Sato, V. (1998). Cultured microalgae as aquaculture feeds.
Journal of Marine Biotechnology, 75, 65-70.
Dufossé, L., Galaup, P., Yaron, A., Arad, S.M., Blanc, P., Murthy, K.N.C., and Ravishankar,
G.A. (2005). Microorganisms and microalgae as sources of pigments for food use: a
scientific oddity or an industrial reality?. Trends in Food Science and Technology, 16,
Microalgae in Novel Food Products 31
Dutta, D., De, D., Chaudhuri, S., and Bhattacharya, S.K. (2005). Hydrogen production by
Cyanobacteria. Microbial Cell Factories, 4, 36-46.
Fábregas, J., Otero, A., Dominguez, A., and Patino, M. (2001). Growth rate of the microalga
Tetraselmis suecica changes the biochemical composition of Artemia species. Marine
Biotechnology, 3, 256-263.
Faure, H., Fayol, V., Galabert, C., Grolier, P., Moel, G.L., Steghens, J., Kappel, A.V., Nabet,
F. (1999). Carotenoids: 1. Metabolism and physiology. Annales de Biologie Clinique, 57,
Feldheim, W. (1972). Studies on use of microalgae in human nutrition. 1. Nutrition tests with
algae containing diets in Thailand. International Journal for Vitamin and Nutrition
Research, 42, 600-606. Cited by Becker, E.W. (1988).
Ferruzi, M.G., and Blakeslee, J. (2007). Digestion, absorption, and cancer preventive activity
of dietary chlorophyll derivatives. Nutrition Research, 27, 1-12.
Fevrier, C., and Seve, B. (1975). Incorporation of Spirulina maxima in pig diets. Annales de
la Nutrition et de l’Alimentation, 29, 625-650.
Fidalgo, J.P., Cid, A.T.E., Sukenik, A., and Herrero, C. (1998). Effects of nitrogen source
and growth phase on proximate biochemical composition, lipid classes and fatty acid
profile of the marine microalgae Isochrysis galbana. Aquaculture, 166, 105-116.
Ghys, A., Bakkere, E., Hornstra, G., Van der Hout, M. (2002). Red blood cell and plasma
phospholipid arachidonic and docosahexaenoic acid levels at birth and cognitive
development at 4 years of age. Early Human Development, 69, 83-90.
Ginzberg, A., Cohen, M., Sod-Moriah, U., Shany, S., Rosenshtrauch, A., and Arad, S.
(2000). Chickens fed with biomass of the red microalga Porphyridium sp. have reduced
blood cholesterol level and modified fatty acid composition in egg yolk. Journal of
Applied Phycology, 12, 325-330.
Glazer, A.N. (1994). Phycobiliproteins - a family of valuable, widely used fluorophores.
Journal of Applied Phycology, 6, 105-112.
Gomes, E., Dias, J., Silva, P., Valente, L., Empis, J., Gouveia, L., Bowen, J., and Young, A.
(2002). Utilization of natural and synthetic sources of carotenoids in the skin
pigmentation of gilthead seabream (Sparus aurata). European Food Research and
Technology, 214, 287–293.
Gouveia, L., Veloso, V., Reis, A., Fernandes, H.L., Empis, J., and Novais, J.M. (1996a).
Chlorella vulgaris used to colour egg yolk. Journal of the Science of Food and
Agriculture, 70, 167–172.
Gouveia, L., Veloso, V., Reis, A., Fernandes, H.L., Empis, J., and Novais, J.M. (1996b).
Evolution of pigment composition in Chlorella vulgaris. Bioresource Technology, 57,
Gouveia, L., Gomes, E., and Empis, J. (1996c). Potential use of a microalgal (Chlorella
vulgaris) in the pigmentation of rainbow trout (Oncorhynchus mykiss) muscle. Zeitschrift
fur Lebensmittel Untersuchung und Forschung, 202, 75-79.
Gouveia, L., Gomes, E., and Empis, J. (1997) Use of Chlorella vulgaris in rainbow trout,
Oncorhynchus mykiss, diets to enhance muscle pigmentation. Journal of Applied
Aquaculture, 7, 61–70.
L. Gouveia. A. P. Batista, I. Sousa et al. 32
Gouveia, L., Choubert, G., Gomes, E., Rema, P., and Empis, J. (1998). Use of Chlorella
vulgaris as a carotenoid source for salmonids: Effect of dietary lipid content on
pigmentation, digestibility and muscular retention. Aquaculture International, 6, 269–
Gouveia, L., Choubert, G., Gomes, E., Pereira, N., Santinha, J., and Empis, J. (2002).
Pigmentation of gilthead seabream, Sparus aurata (Lin 1875), using Chlorella vulgaris
(Chlorophyta, Volvocales) microalga. Aquaculture. Research, 33, 987-993.
Gouveia, L., Rema, P., Pereira, O., and Empis, J. (2003). Colouring ornamental fish
(Cyprinus carpio and Carassius auratus) with microalgal biomass. Aquaculture
Nutrition, 9, 123–129.
Gouveia, L., and Rema, P. (2005). Effect of microalgal biomass concentration and
temperature on ornamental goldfish (Carassius auratus) skin pigmentation. Aquaculture
Nutrition, 11, 19-23.
Gouveia, L., Batista, A.P., Raymundo, A., Sousa, I., and Empis, J. (2006). Chlorella vulgaris
and Haematococcus pluvialis biomass as colouring and antioxidant in food emulsions.
European Food Research and Technology, 222, 362-367.
Gouveia, L., Batista, A.P., Miranda, A., Empis, J., and Raymundo, A. (2007a). Chlorella
vulgaris biomass used as colouring source in traditional butter cookies. Innovative Food
Science and Emerging Technologies, 8, 433-436.
Gouveia, L., Coutinho, C., Mendonça, E., Batista, A.P., Sousa, I., Bandarra, N.M., and
Raymundo, A. (2007b). Sweet biscuits with Isochrysis galbana microalga biomass as a
functional ingredient. Journal of the Science of Food and Agriculture, In press.
Granger, C., Barey, P., Combe, N., Veschambre, P., and Cansell, M. (2003). Influence of the
fat characteristics on the physicochemical behaviour of oil-in-water emulsions based on
milk proteins-glycerol esters mixtures. Colloids and Surfaces B: Biointerfaces, 32, 353-
Gross, R., Gross, U., Ramirez, A., Cuadra, K., Collazos, C., and Feldheim, W. (1978).
Nutritional tests with green Scenedesmus with health and malnourished children. Archiv
fur Hydrobiologie, Beihefte Ergebnisse der Limnologie, 11, 161-173.
Gross, U., and Gross, R. (1978). Acceptance and product selection of food fortified with the
microalga Scenedesmus. Archiv fur Hydrobiologie, Beihefte Ergebnisse der Limnologie,
Guill-Guerrero, J.L., Navarro-Juárez, R., López-Martínez, J.C., Campra-Madrid, P.,
Rebolloso-Fuentes, M.M. (2004). Functional properties of the biomass of the three
microalgal species. Journal of Food Engineering, 65, 511-517.
Hallmann, A. (2007). Algal transgenics and biotechnology. Transgenic Plant Journal, 1, 81-
Han, L., Cui, J.G., and Huang, C.S. (2003). Bioactive polyhydroxy sterols and their
sapogenins from marine organisms. Acta Chimica Sinica, 23, 305-311.
Harel, M., and Clayton, D. (2004). Feed formulation for terrestrial and aquatic animals. US
Patent 20070082008 (WO/2004/080196).
Harker, M., Tsavalos, A.J., and Young, A.J. (1996). Autotrophic growth and carotenoid
production of Haematococcus pluvialis in a 30 liter air-lift photobioreactor. Journal of
Fermentation and Bioengineering, 82, 113-118.
Microalgae in Novel Food Products 33
Hintz, H.F., and Heitmann, H. (1967). Sewage-grown algae as a protein supplement for
swine. Animal Production, 9, 135-141.
Hintz, H.F., Heitmann, H., Weird, W.C., Torell, D.T., and Meyer, J.H. (1966). Nutritive
value of algae grown on sewage. Journal of Animal Science, 25, 675-681.
Hoseney, R.C., Wade, P., and Finley, J.W. (1988). Soft wheat products. In Y. Pomeranz (Ed),
Wheat Chemistry and Technology, volume II, 3
edition (pp. 407-456). American
Association of Cereal Chemists Monograph Series.
Houzé, G., Cases, E., Colas, B., and Cayot, P. (2005). Viscoelastic properties of acid milk gel
as affected by fat content at low level. Interational Dairy Journal, 15, 1006-1016.
International Society for the Study of Fatty Acids and Lipids (ISSFAL) (2004).
Recommendations for dietary intake of polyunsaturated fatty acids in healthy adults.
Jacket, J. (1974). Utilisations biologiques des Spirulines. Bulletin de l’Académie veterinaire
de France, 47, 133-143.
Jespersen, L., Strømdahl, L.D., Olsen, K., and Skibsted, L.H. (2005). Heat and light stability
of three natural blue colorants for use in confectionery and beverages. European Food
Research and Technology, 220, 261–266
Kato, T. (1994). Blue pigment from Spirulina. New Food Industry, 29, 17-21.
Kenneth, G.S. (1989). Pigmentation supplements for animal feed compositions. United States
Patent, nº 4.871.551.
Kusmic, C., Barsacchi, R., Barsanti, L., Gualteri, P., and Passarelli, V. (1999). Euglena
gracilis as a source of the antioxidant vitamin E. Effects of culture conditions in the wild
strain and in the natural mutant WZSL. Journal of Applied Phycology, 10, 555-559.
Lazo, P., Dinis, M.T., Holt, J., Faulk, C., and Arnold, C. (2000). Co-feeding microparticulate
diets with algae: toward eliminating the need of zooplankton at first feeding in larval red
drum (Sciaenops ocellatus). Aquaculture, 188, 339-351.
Liu, C.P., and Lin, L.P. (2001). Ultrastructural study and lipid formation of Isochrysis sp.
CCMP1324. Botanical Bulletin Academia Sinica, 42, 207-214.
Lorenz, R.T., and Cysewski, G.R. (2000). Commercial potential for Haematococcus
microalgae as a natural source of astaxanthin. Trends in Biotechnology, 18, 160-167.
Luiten, E.E.M., Akkerman, I., Koulman, A., Kamersmans, P., Reith, H., Barbosa, M.J.,
Sipkema, D., and Wijffels, R.H. (2003). Realizing the promises of marine biotechnology.
Biomolecular Engineering, 20, 429-439.
Madiedo, G., and Sunde, M. (1964). The effect of algae, dried lake weed, alfalfa and
ethoxyquin on yolk colour. Poultry Science, 43, 1056-1061.
Marusich, W.L., De Ritter, E., and Bauerfeind, J.C. (1960). Evaluation of carotenoid
pigments for colouring egg yolks. Poultry Science, 40, 1338-1345.
McClements, D.J. (1999). Food Emulsions: Principles, Practice and Techniques. CRC Press.
Molina Grima, E., Belarbi, E.H., Acién Fernández, F.G. Robles Medina, A., and Chisti, Y.
(2003). Recovery of microalgal biomass and metabolites: process options and economics.
Biotechnology Advances, 20, 491-515.
Muller-Feuga, A. (2000). The role of microalgae in aquaculture: situation and trends. Journal
of Applied Phycology, 12, 527-534.
Naas, K.E., Naess, T., and Harboe, T. (1992). Enhanced 1
feeding of Halibut Larvae
(Hippoglossus hippoglossus L) in green water. Aquaculture, 105, 143-156.
L. Gouveia. A. P. Batista, I. Sousa et al. 34
Natrah, F., Yosoff, F.M. Shariff, M., Abas, F., and Mariana, N.S. Screening of Malaysian
indigenous microalgae for antioxidant properties and nutritional value. Journal of
Applied Phycology, In press (DOI 10.1007/s10811-007-9192-5).
Nègre-Sadargues, G., Castillo, R., Petit, H., Sancé, S., Martinez, R.G., Milicua, J.C.,
Choubert, G., and Trilles, J.P. (1993). Utilization of synthetic carotenoids by the prawn
Panaeus japonicus reared under laboratory conditions. Aquaculture, 110, 151-159.
Nunes, M.C., Batista, P., Raymundo, A., Alves, M.M., and Sousa, I. (2003). Vegetable
proteins and milk puddings. Colloids and Surfaces B: Biointerfaces, 31, 21-29.
Nunes, M.C., Raymundo, A., and Sousa, I. (2006). Rheological behaviour and microstructure
of pea protein / κ−carrageenan / starch gels with different setting conditions. Food
Hydrocolloids, 20, 106-113.
Olaizola, M. (2003). Commercial development of microalgal biotechnology: from the test
tube to the marketplace. Biomolecular Engineering, 20, 459-466.
Omenn, G.S., Goodman, G.E., Thornquist, M.D., Balmes, J., Cullen, M.R., Glass, A., Keogh,
J.P., Meyskens, F.L., Valanis, B., Williams, J.H., Barnhart, S., Cherniack, M.G.,
Brodkin, C.A., and Hammar, S. (1996). Risk factors for lung cancer and for intervention
effects in CARET, the beta-carotene and retinol efficacy trial. Journal of the National
Cancer Institute, 88, 1550-1559.
Oren, A. (2005). A hundred years of Dunaliella research: 1905-2005. Saline Systems, 1, 2.
Ötles, S., and Pire, R. (2001). Fatty acid composition of Chlorella and Spirulina microalgae
species. Journal of AOAC International, 84, 1708-1714.
Özkanli, O., and Kaya, A. (2007). Storage stability of butter oils from sheep’s non-
pasteurized and pasteurized milk. Food Chemistry, 100, 1026-1031.
Passos, R., Lagreze, F., Moriel, D., Bonfim, T., Gouveia, L., Maraschin, M. and Beirão, L.
(2007). Pigmentation of pacific white shrimp (Litopenaeus vannamei, Boone, 1931) with
carotenoids from natural sources (in preparation).
Piteira, F., Nunes, M.C., Raymundo, A., and Sousa, I. (2004). Effect of principal ingredients
on quality of cookies with dietary fibre. In P.A. Williams, and G.O. Phillips (Eds), Gums
and Stabilisers for the Food Industry 12 (pp. 475-483). Cambridge, UK: Royal Society of
Planas, M., and Cunha, I. (1999). Larviculture of marine fish: problems and perspectives.
Aquaculture, 177, 171-190.
Ponis, E., Probert, I., Véron, B., Mathieu, M., and Robert, R. (2006). New microalgae for the
Pacific oyster Crassostrea gigas larvae. Aquaculture, 253, 618-627.
Pulz, O., and Gross, W. (2004). Valuable products from biotechnology of microalgae.
Applied Microbiology and Biotechnology, 65, 635-648.
Radmer, R.J., and Parker, B.C. (1994). Commercial applications of algae: opportunities and
constraints. Journal of Applied Phycology, 6, 93-98.
Rampon, V., Brossard, C., Mouhous-Riou, N., Bousseau, B., Llamas, G., and Genot, C.
(2004). The nature of the apolar phase influences the structure of the protein emulsifier in
oil-in-water emulsions stabilized by bovine serum albumin. A front-surface fluorescence
study. Advances in Colloid and Interface Science, 108-109, 87-94.
Raja, R., Hemaiswarya, S., and Rengasamy, R. (2007). Exploitation of Dunaliella for β-
carotene production. Applied Microbiology and Biotechnology, 74, 517-523.
Microalgae in Novel Food Products 35
Raymundo, A., Franco, J.M., Empis, J., and Sousa, I. (2002). Optimization of the
composition of low-fat oil-in-water emulsions stabilized by white lupin protein. Journal
of the American Oil Chemists Society, 79, 783-790.
Raymundo, A., Gouveia, L., Batista, A.P., Empis, J., and Sousa, I. (2005). Fat mimetic
capacity of Chlorella vulgaris biomass in oil-in-water food emulsions stabilised by pea
protein. Food Research International, 38, 961-965.
Regulation (EC) No 1831/2003 of the European Parliament and the Council of 22 September
2003 on additives for use in animal nutrition. Official Journal of the European Union,
Regulation (EC) No 258/1997 of the European Parliament and the Council of 27 January
1997 on novel foods and food ingredients. Official Journal of the European Union,
Reis, A., Mendes, A., Lobo-Fernandes, H., Empis, J.A., and Maggiolly-Novais, J. (1998).
Production, extraction and purification of phycobiliproteins from Nostoc sp. Bioresource
Technology, 66, 181-187.
Reitain, K., Rainuzzo, J.R., Oie, G., and Olsen, Y. (1997). A review of the nutritional effects
of algae in marine fish larvae. Aquaculture, 155, 207-221.
Rema, P., and Gouveia, L. (2005). Effect of various sources of carotenoids on survival and
growth of goldfish (Carassius auratus) larvae and juvenile. Journal of Animal and
Veterinary Advances, 4, 654-658.
Reinehr, C.O., and Costa, J.A. (2006). Repeated batch cultivation of the microalga Spirulina
platensis. World Journal of Microbiology and Biotechnology, 22, 937-943.
Romay, C.H., Gonzalez, R., Ledon, N., Remirez, D., and Rimbau, V. (2003). Phycocyanin: a
biliprotein with antioxidant, anti-inflammatory and neuroprotective effects. Current
Protein and Peptide Science, 4, 207-216.
Santipanichwong, R. and Suphantarika, M. (2007). Carotenoids as colorants in reduced-fat
mayonnaise containing spent brewer's yeast b-glucan as a fat replacer. Food
Hydrocolloids, 21, 565-574.
Schilderman, P.A.E.L., ten Vaarwerk, F.J., Lutgerink, J.T., Van der Wurff, A., ten Hoor, F.,
and Kleinjans, J.C.S. (1995). Induction of oxidative DNA damage and early lesions in rat
gastro-intestinal epithelium in relation to prostaglandin H synthese-mediated metabolism
of butylated hydroxyanisole. Food and Chemical Toxicology, 33, 99-109.
Segner, H., Arend, P., Von Poeppinghausen, K., and Schmidt, H. (1989). The effect of
feeding astaxanthin to Oreochromis nioloticus and Colisa labiosa on the histology of the
liver. Aquaculture, 79, 381-390.
Sekar, S., and Chandramohan, M. (2007). Phycobiliproteins as a commodity: trends in
applied research, patents and commercialization. Journal of Applied Phycology, In Press
Shahidi, F., Metusalach, J., and Brown, J.A. (1998). Carotenoids pigments in seafoods and
aquaculture. Critical Reviews in Food Science and Nutrition, 38, 1-67.
Shimamatsu, H. (2004). Mass production of Spirulina, an edible microalga. Hydrobiologia,
Sidhu, K.S. (2003). Health benefits and potential risks related to consumption of fish or fish
oil. Regulatory Toxicology and Pharmacology, 38, 336-344.
L. Gouveia. A. P. Batista, I. Sousa et al. 36
Simopoulos, A.P. (2002). The importance of the ratio of omega-6/omega-3 essential fatty
acids. Biomedicine and Pharmacotherapy, 56, 365-379.
Singh, S., Kate, B.N., and Banerjee, U.C. (2005). Bioactive compounds from Cyanobacteria
and Microalgae: na overview. Critical Reviews in Biotechnology, 25, 73-95.
Soletto, D., Binaghi, L., Lodi, A., Carvalho, J.C.M., and Converti, A. (2005). Batch and fed-
batch cultivations of Spirulina platensis using ammonium sulphate and urea as nitrogen
sources. Aquaculture, 243, 217-224.
Sommer, T.R., Potts, W.T., and Morrissy, N.M. (1991). Utilization of microalgal astaxanthin
by rainbow trout. Aquaculture, 94, 79-88.
Sommer, T.R., Da Souza, F.M.L., and Morrisy, N.M. (1992). Pigmentation of adult rainbow
trout, Oncorhynchus mykiss, using the green alga Haematococcus pluvialis. Aquaculture,
Spolaore, P., Joannis-Cassan, C., Duran, E., and Isambert, A. (2006). Commercial
applications of Microalgae- review. Journal of Bioscience and Bioengineering, 101, 87-
Stahl, W.; Sies, H. (2005). Bioactivity and protective effects of natural carotenoids.
Biochimica et Biophysica Acta, 1740, 101-107.
Tang, H.F., Yi, Y.H., and Yao, X.S. (2002). Progress in the study of marine steroids. Journal
of Marine Drugs (Chinese), 3, 38-47.
Tapiero, H.; Townsend, D.M.; Tew, K.D. (2004). The role of carotenoids in the prevention of
human pathologies. Biomedicine and Pharmacotherapy, 58, 100-110.
Thies, F., Garry, J.M., Yagoob, P., Rerkasem, K., Williams, J., Shearman, C.P., Gallagher,
P.J., Calder, P.C., and Grimble, R.F. (2003). Association of n-3 polyunsaturated fatty
acids with stability of atherosclerotic plaques: a randomized controlled trial. Lancet, 361,
Torrissen, O.J. (1984). Pigmentation of salmonids-effect of carotenoids in eggs and star-
feeding diet on survival and growth rate. Aquaculture, 43, 185-193.
Torrissen, O.J., and Christiansen, R. (1995). Requirements of carotenoids in fish diets.
Journal of Ichthylogy, 11, 225-230.
Tsuchiya, M., Scita, G., Freisleben, H.L., Kagan, V.E., and Packer, L. (1992). Antioxidant
radical-scavenging activity of carotenoids and etinoids compared to β-tocopherol.
Methods of Enzymology, 213, 460 – 472.
Van den Berg, H, Faulks, R., Granado, H.F., Hirschberg, J., Olmedilla, B., Sandmann, G.,
Southon, S., and Stahl, W. (2000). The potential for the improvement of carotenoid levels
in foods and the likely systemic effects. Journal of the Science of Food and Agriculture,
Vélez-Ruiz, J.F., González-Tomás, L., and Costell, E. (2005). Rheology of dairy custard
model systems: influence of milk-fat and hydrocolloid type. European Food Research
and Technology, 221, 342-347.
Volkman, J.K., Jeffery, S.W., Nichols, P.D., Rogers, G.I., and Garland, C.D. (1989). Fatty
acid and lipid composition of 10 species of microalgae used in mariculture. Journal of
Experimental Marine Biology and Ecology, 128, 219-240.
Volkman, J.K. (2003). Sterols in microrganisms. Applied Microbiology and Biotechnology,
Microalgae in Novel Food Products 37
Waldenstedt, L., Inborr, J., Hansson, I., and Elwinger, K. (2003). Effects of astaxanthin-rich
algal meal (Haematococcus pluvialis) on growth performance, caecal campylobacter and
clostridial counts and tissue astaxanthin concentration of broiler chickens. Animal Feed
Science and Technology, 18, 119-132.
Wang, C., Harris, W.S., Chung, M., Lichtenstein, A.H., Balk, E.M., Kupelnick, B., Jordan,
H.S., and Lau, J. (2006). n-3 Fatty acids from fish or fish-oil supplements, but not a-
linolenic acid, benefit cardiovascular disease outcomes in primary and secondary
prevention studies: a systematic review. American Journal of Clinical Nutrition, 84, 5–
Wikfors, G.H., Gladu, P.K., and Patterson, G.W. (1991). In search of the ideal diet for
oysters: recent progress with emphasis on sterols. Journal of Shellfish Research, 10, 292-
Wikfors, G.H., Ferris, G.E., and Smith, B.C. (1992). The relationship between gross
biochemical composition of cultured algal foods and growth of the hard clam,
Mercenaria mercenaria (L.). Aquaculture, 108, 135-154.
Wroble, M., Mash, C., Williams, L., and McCall, R.B. (2002). Should long chain
polyunsaturated fatty acids be added to infant formula to promote development? Applied
Developments in Phychology, 23, 99-112.
Xu, Z., Yan, X., Pei, L, Luo, Q., and Xu, J. Changes in fatty acids and sterols during batch
growth of Pavlova viridis in photobioreactor. Journal of Applied Phycology, In press
Yamaguchi, K. (1997). Recent advances in microalgal bioscience in Japan, with special
reference to utilization of biomass and metabolites: a review. Journal of Applied
Phycology, 8, 487-502.
Yap, T.N., Wu, J.F., Pond, W.G., and Krook, L. (1982). Feasibility of feeding Spirulina
maxima, Arthrospira platensis or Chlorella sp. to pigs weaned to a dry diet at 4 to 8 days
of age. Nutritional Reports International, 35, 543-552.
Yen, W.J., and Chen, B.H. (1995). Isolation of xanthophylls from Taiwanese orange peels
and their effects on the oxidation stability of soybean oil. Food Chemistry, 53, 417-425.
Yokoyama, A., and Miki, W. (1995). Composition and presumed bio-synthetic pathway of
carotenoids in the astaxanthin-producing bacterium Agrobacterium aurantiacum. FEMS
Microbiology Letters, 128, 139-144.
Yuang, J.P., Chen, F. (2000). Purification of trans-astaxanthin from a high-yielding
astaxanthin ester-producing strain of the microalga Haematococcus pluvialis. Food
Chemistry, 68, 443-448.