Content uploaded by Celia Hugo
Author content
All content in this area was uploaded by Celia Hugo on Sep 10, 2018
Content may be subject to copyright.
Review
Current trends in
natural preservatives
for fresh sausage
products
Celia J. Hugo*and Arno Hugo
Department of Microbial, Biochemical and Food
Biotechnology, University of the Free State, PO Box
339, Bloemfontein, 9300, South Africa (Tel.: D27 (0)
51 4012692; fax: D27 (0)51 4019335; e-mail: hugocj@
ufs.ac.za)
Natural preservatives from bacteria, plants and animals
currently in use in fresh sausage manufacture were investi-
gated. Bacteriocins and organic acids from bacterial origins
showed good antimicrobial activities against pathogens.
Plant-derived antimicrobials could increase the shelf-life of
fresh sausages and in some cases also decrease lipid oxidation
and decrease colour loss. Chitosan was the only animal-
derived antimicrobial investigated and also increased shelf
life of fresh sausages. It was evident that the natural antimicro-
bials would perform even better in combination with other
natural antimicrobials, or lowered levels of synthetic antimi-
crobials or other hurdles such as specific packaging material.
Introduction
Sausages are products manufactured from fresh commi-
nuted meats from different meat species, such as pork,
beef, chicken, fish and buffalo (Raju, Shamasundar, &
Udupa, 2003; Sachindra, Sakhare, Yashoda, & Rao, 2005;
Sallam, Ishioroshi, & Samejima, 2004). The comminuted
meats are then modified by various processing technologies
and stuffed in a casing to yield specific sensory and storage
characteristics (Savic, 1985). Preservatives are commonly
used to enhance their quality, shelf life and safety
(Sultana et al., 2014).
Fresh sausages are highly perishable products since it is
manufactured from fresh ground meat, is favourable for
microbial growth of spoilage and pathogenic organisms,
has a high fat content favourable for lipid oxidation, is
stored in oxygen semi-permeable packaging and is kept at
refrigeration temperatures. These products, therefore,
need to be preserved to maintain the quality of the products.
The antimicrobial and/or antioxidant preservatives
currently employed in these products are chemicals, e.g.
sulphur dioxide (SO
2
) as antimicrobial and colour preserva-
tive (Romans, William, Carloson, Greaser, & Jones, 2001)
and/or synthetic antioxidants such as butylated hydroxyto-
luene (BHT), butylated hydroxyanisole (BHA) and propyl
gallate (Kim, Cho, & Han, 2013).
The synthetic preservatives have many advantages but
have come under the scrutiny of consumers. These preser-
vatives include nitrates, benzoates, sulfites, sorbates, form-
aldehyde and others pay possess life-threatening side
effects (Sultana et al., 2014). Gunnison, Jacobsen, and
Schwartz (1987) have stated that the use of sulphite as a
preservative can trigger different allergic reactions in sul-
phite hypersensitive consumers. Symptoms such as asthma,
urticaria, abdominal pains, nausea, diarrhoea, seizures and
anaphylactic shock resulting in death have been recorded.
Antioxidants such as BHT and BHA are associated with
possible carcinogenic effects although their use has been
restricted (Kim et al., 2013). These health dangers have re-
sulted in the need and demand by consumers for using nat-
ural preservatives (Ba~
n
on, D
ıaz, Rodr
ıguez, Garrido, &
Price, 2007).
The research on natural preservatives included investiga-
tions of the antimicrobial and antioxidant characteristics of
compounds derived from microbial, plant and animal sour-
ces (Dillon & Board, 1994). Plant derived preservatives
(grape, rosemary extract, etc.) and animal derived preserva-
tives (e.g., chitosan from fish) have been shown to have
antioxidant and antimicrobial properties (Ba~
n
on et al.,
2007). Some plant extract products, e.g. rosemary, even
have health benefits such as liver protective and anti-
tumour activities (Balentine, Crandall, O’Bryan, Duong,
& Pohlman, 2006).
The aims of this review were to give a definition and
classification of sausages and fresh sausages and illustrate
the factors influencing the quality of fresh sausages. The
chemical antimicrobials and antioxidants traditionally
used for fresh sausage preservation will be mentioned. Nat-
ural antimicrobials and/or antioxidants from microbial-,
plant- and animal-derived compounds and its use in fresh
* Corresponding author.
http://dx.doi.org/10.1016/j.tifs.2015.05.003
0924-2244/Ó2015 Elsevier Ltd. All rights reserved.
Trends in Food Science & Technology 45 (2015) 12e23
sausages will then be discussed in terms of mode of action,
safety and applications.
Classification of sausage products
Because sausage manufacturing has been practiced
before recorded history, it is not certain how and when the
first sausage was produced (Savic, 1985). The word
“sausage”, however, is derived from saussiche (Old Norman
French), sals
ıcia (Late Latin) or from salsus (Latin) which
means “salted” (Harper, 2001e2014). According to Rust
(1987) the preparation of sausages began with a simple pro-
cess of salting and drying meats which aided in the preser-
vation of the sausages. Flavourings and spices were added
to improve the flavour of the product. The product was
then stuffed in a container, namely the gastrointestinal tract
of animals, to make the product more convenient to eat.
Sausages are defined as comminuted seasoned meats,
stuffed into casings, and may be smoked, cured, fermented
and heated. A wide variety of sausages products can be pro-
duced by altering the meat formulation, processing temper-
ature, types of casings and the particle size of the casings
(Savic, 1985). A classification of sausages based on charac-
teristics, is given in Table 1. This review will, however,
focus only on fresh sausages.
Fresh sausages
According to the Food Safety and Inspection Service
(FSIS) of the United States Department of Agriculture
(USDA-FSIS, 2014), fresh sausages are a coarse or finely
comminuted (reduced to minute particles) meat food product
prepared from one or more kinds of meat, or meat and meat
byproducts (e.g., heart, kidney, liver). They may contain not
more than 3% water of the total ingredients in the product.
Fresh sausages are usually seasoned, frequently cured, and
may contain binders and extenders (e.g., wheat flour, non-
fat dry milk). They must be refrigerated and thoroughly
cooked before eating. Although plenty of varieties of fresh
sausages do exist, the content of the most known varieties
is illustrated in Table 2.
Factors influencing the quality of fresh sausages
The quality of fresh sausages is of major importance
since the shelf-life of the products depends on this aspect.
Spoilage of food involves a complex process and excessive
amounts of food may be lost, which results in high eco-
nomic losses or even pose health hazards (Al-Sheddy, Al-
Dagal, & Bazaraa, 1999; Liu, Yang, & Li, 2006).
Spoilage of fresh sausages may result in changes in the
sensory (colour, odour, flavour, texture) characteristics of
the product which may be unacceptable for consumers.
These changes may be brought about by proteolysis, lipol-
ysis and lipid oxidation in the absence of micro-organisms.
Microbial growth is, however, by far the most important
factor causing spoilage of fresh products (Zhou, Xu, &
Liu, 2010).
Microbial composition
Meat in general is an ideal growth medium for a wide
range of microorganisms (Mathenjwa, Hugo, Bothma, &
Hugo, 2012; Russo, Ercolini, Mauriello, & Villani, 2006;
Zhang, Kong, Xiong, & Sun, 2009). Aerobic colony counts
may range from 1.5 10
3
e2.1 10
8
cfu/g for fresh
Table 1. Sausage classification (adapted from Savic, 1985).
Classification Characteristics Examples
Raw sausages
Fresh Made from fresh comminuted, uncured, non-smoked meats.
Must be refrigerated prior to heating by the consumer.
Breakfast sausage (USA), boerewors
(South Africa), bratwurst (Germany),
merguez (North Africa), siskonmakkara
(Finland)
Fermented Made from comminuted, cured or uncured, fermented and
often smoked meats. Not heat-processed.
Semidry
(quickly fermented)
Stuffed in medium- and large-diameter artificial casings.
“Tangy” flavour produced by fermentation. Length of smoking
and fermentation depends on type but rarely exceeds a few days.
Improved stability of stored refrigerated.
Variety of summer sausages, cervelats,
mettwursts, Lebanon bologna (USA)
Dry
(slowly fermented)
Different types of salamis, dro€
ewors
(South Africa, not fermented)
Heat-processed sausages
Smoked precooked Mostly comminuted, cured, non-fermented. Final cooking
before consumption
Chinese pork sausages, kielbasa
Emulsion-type Made from comminuted well-homogenized cured meats,
fat, water and seasoning. Usually smoked, slightly cooked.
Ready-to-eat product.
Frankfurters, wieners, bologna,
mortadella
Cooked Made from previously comminuted cooked fresh or
cured raw materials. Final cooking after stuffing. With or without
smoking. Ready-to-eat product.
Liver sausage, Braunschweiger
13C.J. Hugo, A. Hugo / Trends in Food Science & Technology 45 (2015) 12e23
Table 2. Content of the major fresh sausage varieties produced world-wide.
Variety Meat Fat Other ingredients Casing Reference
Breakfast sausage
(United States
of America)
Meat and meat by products
of multiple species. May
contain mechanically-separated
product up to 20% of the
meat portion.
Not more than 50%
by weight
Salt, pepper, sage. Binders
and extenders up to 3.5%.
Paprika not permitted.
USDA-FSIS (1999, 2014),http://en.wikipedia.
org/wiki/Breakfast_sausage, accessed
on 25/11/2014
Fresh pork sausage
(USA)
Pork, no pork by products Not more than 50%
by weight
Salt, pepper. Flavouring:
either sage and sugar, or
sage, chilli and ginger.
Paprika, binders or
extenders not permitted.
Narrow (26e28 mm)
pig casing
USDA-FSIS (1999, 2014), Savic (1985)
Fresh beef sausage
(USA)
Beef, no beef by products.
May contain mechanically-
separated beef up to 20%
of the meat portion.
Not more than 30%
by weight
Salt, pepper, red pepper,
chilli, ginger, cardamom,
fenugreek, sugar. Paprika,
binders or extenders
not permitted.
Sheep or goat. Narrow
(16e18 mm),
narrow-medium
(18e22 mm), medium
(20e22 mm) and wide
(22e24 mm)
USDA-FSIS (1999, 2014), Savic (1985)
Whole hog sausage
(USA)
Can use meat parts from
entire hog, including
muscle by-products like
tongue and heart, in
proportions consistent with
the natural animal.
Not more than 50%
by weight
USDA-FSIS (1999, 2014)
Italian sausage (Italy) At least 85% pork meat.
May contain mechanically-
separated pork up to 20% of
the meat portion.
Not more than 35%
of finished product
Salt, pepper, fennel
and/or anise. Optional:
spices (including paprika),
flavourings, red or green
peppers, onions, garlic,
parsley, sugar, dextrose
and corn syrup.
USDA-FSIS (1999, 2014)
Boerewors
(South Africa)
At least 90% meat of the
bovine, ovine, porcine or
caprine species. No by-products
or mechanically separated meat
are permitted
Not more than 30%
by weight
Salt (1e5%), pepper.
Vinegar, herbs, spices
(coriander, nutmeg,
allspice, etc.), harmless
flavourants, cereal products
or starch, permitted food
additives
Natural animal casings Rust, 1987; Romans et al., 2001;
http://en.wikipedia.org/wiki/Boerewors
(accessed on 6/11/2014)
Merguez
(North Africa)
Made from mutton or beef
or a mixture of both
Salt, pepper. Sumac for tartness
and paprika, cayenne pepper
or harissa for red colour
Lamb casing http://www.meatsandsausages.com/
sausage-recipes/merguez (accessed
on 06/11/2014)
Bratwurst
(Germany)
Mainly pork and veal, but also
pork and beef
Salt, pepper, marjoram, caraway,
nutmeg, ginger, white of eggs
32e36 mm hog casings http://www.meatsandsausages.com/
sausage-recipes/bratwurst (accessed
on 25/11/2014)
14 C.J. Hugo, A. Hugo / Trends in Food Science & Technology 45 (2015) 12e23
sausage to 1.4 10
3
e3.1 10
7
cfu/g for frozen sausage
(Farber, Malcolm, Weiss, & Johnston, 1988) and yeast
counts varying from 5.0 10
3
e4.7 10
8
cfu/g for fresh
sausages (Dalton, Board, & Davenport, 1984; Dillon &
Board, 1994). The genera involved in spoilage of fresh
meats and sausages were discussed by Cocolin et al.
(2004); Coma (2008); Crowley et al. (2005); Dalton et al.
(1984); Dillon and Board (1994); Huffman (2002), and
Olofsson, Ahrn
e, and Molin (2007).
A number of pathogens are associated with ground beef
(Eisel, Linton, & Muriana, 1997; Farber et al., 1988;
Huffman, 2002; Hussain, Mahmood, Akhtar, & Khan,
2007; Little, Richardson, Owen, de Pinna, & Threlfall,
2008; Mrema, Mpuchane, & Gashe, 2006; Nortj
e,
Vorster, Greebe, & Steyn, 1999; Vorster, Greebe, &
Nortj
e, 1994). According to the United States Department
of Agriculture (USDA-FSIS, 1999), sausage makers should
ensure that their products are not contaminated by patho-
gens such as Listeria,Escherichia coli O157, Salmonella,
Trichinae and Staphylococcus enterotoxin.
The intrinsic factors affecting bacterial growth, and
therefore the spoilage potential of fresh sausage products,
include pH, which should not be less than 5.5 (Cocolin
et al., 2004; Romans et al.,2001); nutrient availability; wa-
ter activity which is equal to, or higher than 0.97 (Cocolin
et al., 2004; Romans et al., 2001; Thomas, Anjaneyulu, &
Kondaiah, 2008); and oxidation/reduction potential.
The extrinsic factors include temperature where fresh
sausages are usually stored at or below 4 C before con-
sumption (Cocolin et al., 2004; Rust, 1987); particle sur-
face area where grinding of the meat increases the
spoilage characteristics; gaseous environment and pack-
aging material (Cannon et al., 1995; Romans et al., 2001).
Free radicals
Apart from microbial spoilage, lipid oxidation or oxida-
tive rancidity is the second most known spoilage factor of
fresh meat and fresh meat products. The grinding of meat
disrupts the integrity of muscle membranes and exposes
the lipid membranes to metal ions, which facilitates interac-
tions between prooxidants and unsaturated fatty acids (Kim
et al., 2013). Lipid oxidation therefore depends on light and
oxygen access, the chemical composition of the meat, stor-
age temperature and technological processes (e.g., grinding).
This will have a negative effect on the quality of the meat
leading to changes in sensory (colour, texture and flavour)
and nutritional quality (Shah, Bosco, & Mir, 2014).
Fresh meat cuts and meat products owe their bright red
colour to the presence of oxymyoglobin. During chilled
storage, this red colour is lost due to exposure to high levels
of oxygen. The red oxymyoglobin is then transformed to
the brown-coloured metmyoglobin (Kim et al., 2013).
Conventional chemical preservation of fresh sausages
Lipid oxidation and microbial growth during storage can
be reduced by applying antioxidant and antimicrobial
agents to the meat products, leading to a retardation of
spoilage, extension of shelf-life, and maintenance of quality
and safety (Kim et al., 2013). Many preservatives used for
this goal, are chemicals.
Antimicrobials
The most commonly used preservative in fresh sausages,
is currently still sulphur dioxide (SO
2
). It is usually added
in the sulphite salt form as sodium metabisulphite
(Varnam & Sutherland, 1995) and expressed as part per
million (ppm) or mg/kg SO
2
(Gould & Russell, 2003).
The antimicrobial effect of the sulphite salts is exerted
through the undissociated SO
2
molecule. The degree of
dissociation is dependant on the pH value and is reduced
under acidic conditions. Even though the pH of meat
(5.2e5.7) has a negative effect on the antimicrobial activity
of the sulphite salts, it is still sufficiently powerful to act as
an antimicrobial (Varnam & Sutherland, 1995). Another
factor that may have an influence on the effectiveness of
SO
2
is the presence of carbonyl compounds (keto- or
aldehyde-groups) that bind with it. Thus for SO
2
to be
effective, not only must the substrate be acidic, but fairly
free of oxygen and sulphite binding compounds (Carr,
Davies, & Sparks, 1976).
Bacteria are much more sensitive to SO
2
than yeasts and
moulds. The bisulphites have lower activity than SO
2
against yeasts, and sulphites have none. Metabisulphite is
more effective against Gram-negative bacteria, especially
Pseudomonas. However, activity against fermentative
Gram-negative bacteria, e.g. the Enterobacteriaceae (Enter-
obacter, Citrobacter, Klebsiella), is less marked possibly
due to adaptation amongst members of this family to this
preservative. Brochothrix thermosphacta, the dominating
spoilage bacteria in British fresh sausages, is also relatively
resistant to sulphite (Varnam & Sutherland, 1995).
The antimicrobial effect of sulphite on fresh pork
sausage was illustrated by Dyett and Shelley (1966).The
results suggested that sausages containing a sulphite con-
centration greater or equal to 450 mg/kg had a lower aero-
bic count. The study also showed that the presence of
400e500 mg/kg SO
2
in minced meat had a negative effect
on the growth of Gram-negative bacteria even at tempera-
tures as high as 22 C and inhibited the growth of patho-
genic organisms such as Staph. aureus and Salmonella
Typhimurium. Therefore, most fresh sausages are by law
preserved by these concentrations of SO
2
.
Originally, research indicated that humans are reason-
ably tolerant to sulphur dioxide and, unless damaging doses
are given, can recover unaffected. Recently, however, cases
concerning the sensitivity of asthmatics to sulphur dioxide
have been reported (Ba~
n
on et al., 2007). Some of these
were life threatening or fatal, due to seizures and anaphy-
lactic shock. It may cause headaches, nausea, and diarrhoea
in some humans (Gunnison et al., 1987). Since some SO
2
is
liberated as gas during cooking, this could give rise to res-
piratory problems, mostly in asthmatic people, thiamine
15C.J. Hugo, A. Hugo / Trends in Food Science & Technology 45 (2015) 12e23
absorption deficiency and disruption of carbohydrate meta-
bolism, particularly in individuals who have an allergic re-
action to SO
2
. The toxic effect is, however, variable in
humans and persons may tolerate different levels (Ba~
n
on
et al., 2007).
Antioxidants
To reduce lipid oxidation in meat products, several syn-
thetic antioxidant preservatives, such as butylated hydroxyl
toluene (BHT), butylated hydroxyanisole (BHA), tert-
butylhydroquinone (TBHQ) and propyl gallate (PG), are
typically used to protect foods from lipid oxidation
spoilage. Antioxidant use in food products is controlled
by regulatory laws of a country or international standards.
In general, the use of synthetic antioxidants is restricted
due to possible carcinogenic effects (Kim et al., 2013).
The mode of action for antioxidants can be by: scavenging
radicals; breaking chain reactions; decomposing peroxides;
decreasing localized oxygen concentrations; and binding
chain initiating catalysts (Shah et al., 2014).
Antibrowning
Sulphur dioxide (SO
2
) has been used in sausages not
only as an antimicrobial but also to improve or maintain
the colour of the sausages (Dyett & Shelley, 1966;
Romans et al., 2001).
Natural antimicrobial and antioxidant preservatives
for fresh sausages
Chemical additives and preservatives are usually
avoided due to possible allergic reactions in sensitive con-
sumers of preserved food. The other major reason, however,
is because consumers in general are nowadays more aware
of the safety of any additives to food and are demanding
natural products (Gyawali & Ibrahim, 2014). Researchers
all over the world are therefore investigating a variety of
safer and natural preservatives as alternatives to chemical
and synthetic preservatives. In fresh meat and especially
fresh sausage production, the alternative preservatives can
be broadly divided into microbial-derived compounds,
plant-derived compounds and animal-derived compounds.
Microbial-derived compounds
Many microorganisms, especially the lactic acid bacteria
(LAB), have the ability to produce antimicrobials to
improve their competitiveness. The compounds produced
by these bacteria have historically long been used to pre-
serve food. These compounds are small-molecular-mass
organic molecules, which are divided into proteins (mainly
bacteriocins) and non-proteins which include organic acids
(lactic acid, propionic acid, butyric acid, acetic acid, etc.),
hydrogen peroxide, diacetyl and other compounds (Sun,
Li, Song, & Zhu, 2011). The application of microbial-
derived compounds in the manufacture of fresh sausages
is depicted in Table 3.
Bacteriocins
Bacteriocins are the most known antimicrobial peptides
produced by lactic acid bacteria. In bacterial metabolism
the bacteriocins are synthesized and secreted by the ribo-
some into the environment. Bacteriocins are known to be
more effective against Gram-positive bacteria (e.g. Listeria
monocytogenes) than Gram-negative ones due to the pres-
ence of the protective outer membrane on the cell mem-
brane of Gram-negative bacteria (Sun et al., 2011).
Bacteriocin production is a natural process during
fermentation of foods. It may, however, be added to foods
in the form of concentrated preservative preparations,
shelf-life extenders or additives. According to Sun et al.
(2011), the bacteriocins can help to reduce the addition of
chemical preservatives in the food industry as well as the
intensity of heat treatments. Many bacteriocins are active
against endospore-forming bacteria and may, therefore, be
applied as another hurdle in combination with other
Table 3. Application of microbial-derived natural preservatives in fresh sausage products.
Microbial preservative Produced from Activity against Product tested Reference
Bacteriocins
Lacticin 3147 Lactococcus lactis
subsp. lactis
Listeria innocua,Clostridium
perfringens, Salmonella Kentucky
Fresh pork sausage Scannell, Ross, Hill, and
Arendt (2000)
Reuterin Lactobacillus reuteri Listeria monocytogenes,
Salmonella spp.
Bratwurst-style fresh
sausage in Turkey
Kuleas
¸an and Cakmakc
¸i (2002)
Organic acids
Citric acid
(sodium citrate)
Salmonella Kentucky Fresh pork sausage Scannell, Hill, Buckley, and
Arendt (1997)
Acetic acid and
sodium lactate mixture
Total plate count (SR)
Lipid oxidation [
Colour loss [
Fresh Italian pork sausage Crist et al. (2014)
Sodium lactate and
sodium acetate mixture
Total aerobic count Merguez sausage Ayachi et al. (2007)
‘[’, increased; SR, significant reduction.
16 C.J. Hugo, A. Hugo / Trends in Food Science & Technology 45 (2015) 12e23
preservation hurdles (G
alvez, Abriouel, Lucas, Jos
e, &
Burgos, 2011). The food composition, interaction of bacte-
riocins with food components, bacteriocin stability, pH and
storage temperature may, however, influence the effective-
ness of bacteriocins (Sun et al., 2011). It is recommended
that the activity of any bacteriocin should be confirmed
through applied studies in food model systems after
in vitro studies have been performed.
Nisin is a heat-stable bacteriocin produced by Lactococ-
cus lactis subsp. lactis and is the only antimicrobial that is
approved for use in more than 50 countries world-wide
(Gyawali & Ibrahim, 2014). Organisms that are inhibited
by nisin include Gram-positive (Staph. aureus, M. luteus)
and spore forming bacteria (Bacillus cereus and Clos-
tridium)(Davies et al., 1999; Rajendran, Nagappan, &
Ramamurthy, 2013). The cytoplasmic membrane of these
bacteria is permeated by nisin, causing leakage of intracel-
lular metabolites and disrupting the membrane potential
(Lucera, Costa, Conte, & Del Nobile, 2012). Since nisin
is ineffective against Gram-negative bacteria and fungi,
its use and application as a broad-spectrum antimicrobial
is restricted (Juneja, Dwivedi, & Yan, 2012). Nisin has
not yet been evaluated in fresh sausages although studies
have been performed on vacuum-packaged fresh beef
which showed L. monocytogenes reduction (Zhang &
Mustapha, 1999). Other studies on cured meat products
have been discussed by Juneja et al. (2012).
Lacticin is another bacteriocin produced by Lactococcus
lactis subsp. lactis. Since the organism producing this bacte-
riocin has GRAS status, the use of this bacteriocin food pro-
duction is also regarded safe (Fallico McAuliffe, Ross,
Fitzgerald, & Hill, 2011). A study by Scannell, Ross, Hill,
and Arendt (2000) on the keeping quality of fresh pork
sausage found that lacticin and nisin performed better
against Gram-positive organisms than sodium metabisul-
phite. The combination of organic acids with either of these
bacteriocins enhanced their antimicrobial activity against
Listeria innocua and Salmonella Kentucky and was even
more effective against Clostridium perfringens. This study
also suggested that lacticin combined with sodium lactate
or sodium citrate can be used as an alternative preservative
of fresh pork sausage since it gave lower total aerobic plate
counts throughout storage than sodium metabisulphite.
Pediocin is produced by Pediococcus acidilactici or P.
pentosaceus and has been shown to be effective against L.
monocytogenes and other Gram-positive pathogens on
meat surfaces (Coma, 2008; Siragusa, Cutter, & Willett,
1999). Pediocin has GRAS status in certain food applica-
tions (Juneja et al., 2012). Research on some meat products
indicated that pediocins (especially pediocin PA-1), could
be more effective than nisin especially when used in com-
bination with nisin, lysoszyme, organic acids, sodium do-
decyl sulphate or ethylenediaminetetraacetic acid
(EDTA). Pediocin has not yet been evaluated in fresh sau-
sages. A study has been performed on fresh chicken to con-
trol L. monocytogenes (Juneja et al., 2012).
Reuterin (b-hydroxypropionaldehyde) is produced by
Lactobacillus reuteri and has a broadspectrum antimicro-
bial activity towards food pathogens and spoilage organ-
isms and has GRAS status. The bio-preservative effect of
reuterin originates from its high resistance to heat, proteo-
lytic and lipolytic enzymes, as well as good solubility in
water. It is stable over a wide range of pH values
(Gyawali & Ibrahim, 2014). Reuterin has a higher antimi-
crobial effect on Gram-negative than on Gram-positive
pathogens. The application of reuterin in a fresh sausage
model system is indicated in Table 3. Furthermore, a study
by El-Ziney, van den Tempel, Debevere, and Jakobsen
(1999) on ground pork found that reuterin at 100 AU/g
reduced E. coli O157:H7 by 5 log cfu/g after 1 day storage
at 4 C while L. monocytogenes was reduced by 3 log cfu/g
after 7 days of storage. It is speculated that reuterin causes
oxidative stress response by modifying the thiol groups in
proteins and small molecules (Langa, van den Tempel,
Debevere, & Jakobsen, 2013).
The combination of bacteriocins with other compounds
usually results in better antimicrobial activities. Nisin mol-
ecules alone, for example, usually interact with food com-
ponents in raw meats, limiting its activity. It also has poor
solubility at close to neutral pH. However, a combination
with other hurdles such as organic acids, lysozyme, chela-
tors, vacuum packaging or MAP, improved its effectivity
against B. thermosphacta, E. coli O157:H7 and L. monocy-
togenes (G
alvez et al., 2011).
Other bacteriocins (e.g. sakacins, carnobacteriocins, bifi-
docins, lactococcins or pentocins) have not yet been evalu-
ated in fresh sausages. On raw meats or poultry meats,
however, they showed variable antimicrobial effects against
pathogenic and spoilage bacteria (G
alvez et al., 2011).
Organic acids
The organic acids are natural antimicrobials produced
during lactic acid fermentation and have generally recog-
nized as safe (GRAS) status for meat products. Application
of these acids on meat surfaces, mainly by spraying or dip-
ping, is a well-known and widely-used practice. Many
studies, as indicated by Mani-L
opez, Garc
ıa, and L
opez-
Malo (2012), have tested the efficacy of organic acids.
Organic acids, however, may have negative impacts on
colour and flavour and it is recommended that sensory
studies should always be applied when an organic acid is
evaluated for possible use as natural antimicrobials in
meat and meat products. Another limiting factor in using
organic acids in fresh meat products is that some acids
(e.g. citric acid) need low pH for optimum antimicrobial ac-
tivity (Mani-L
opez et al., 2012).
According to Mani-L
opez et al. (2012) acetic acid, ace-
tates, diacetates and dehydroacetic acid have effectivity as
antimicrobials against yeasts and bacteria in dairy products
and meat and meat products. Lactic acid and lactates are
effective against bacteria in meat and meat products and
fermented foods while sodium propionate is effective
17C.J. Hugo, A. Hugo / Trends in Food Science & Technology 45 (2015) 12e23
against moulds in meat products. An in vitro study by
Alvarez-Ord
o~
nez, Fern
andez, Bernardo, and L
opez (2010)
indicated that acetic acid is the best antimicrobial against
Salmonella Typhimurium with a decreasing order of effec-
tivity of other organic acids as follows:
acetic >lactic >citric >hydrochloric.
The applications of organic acids in fresh sausage model
systems are given in Table 3. According to G
alvez et al.
(2011), organic acids and salts in conjunction with bacterio-
cins result in increased inactivation of bacteria and inhibi-
tion of growth as well as increased solubility and activity
of bacteriocin molecules. Ayachi, Daoudi, and
Benkerroum (2007) reported that the addition of a mixture
of organic acids (sodium lactate 90% and sodium acetate
10%) at different concentrations (from 0 to 20 g/kg) on
Merguez sausages significantly reduced microbial cell
loads during storage at 8 C. A study by Crist et al.
(2014) indicated that vinegar and sodium lactate mixtures
increased shelf life by reducing total plate counts, however,
lipid oxidation and colour loss increased over time. This
study recommended that antioxidants such as BHA/BHT
should be used in combination with sodium lactate or vin-
egar/sodium lactate mixtures to prevent colour degradation
and rancidity.
Plant-derived compounds
Extracts from fruits, vegetables, herbs and spices are
rich sources of essential oils. The FDA (2014) has recently
published a revised list of plants and generally recognizes
the essential oils, oleoresins and extractives of these plants
as safe. The essential oils (EOs) of leaves (e.g., oregano,
rosemary, thyme, sage, basil, marjoram); flowers or buds
(e.g., clove); bulbs (e.g., onion, garlic); seeds (e.g., parsley,
caraway, nutmeg, fennel); rhizomes (e.g., asafoetida); fruits
(e.g., pepper, cardamom) or other parts (e.g. bark) of plants
are responsible for the antimicrobial (Tiwari, Valdramis,
Bourke, & Cullen, 2011) and antioxidant (Shah et al.,
2014) activities by plants. These EOs have also been used
extensively in foods as flavouring agents and/or for their
medicinal properties since the earliest recorded history
(Tiwari et al., 2011).
The addition of EOs to foods may result in either de-
stroying microbial cells or in inhibiting the production of
secondary metabolites such as mycotoxins (Tiwari et al.,
2011). In general, the EOs are more inhibitory against
Gram-positive than Gram-negative bacteria (Busatta
et al., 2008; Oussalah, Callet, Saucier, & Lacroix, 2007),
however, some EOs from oregano, clove, cinnamon, citral
and thyme are effective against both groups. The antimicro-
bial activity of EO’s are mainly ascribed to the phenolic
compounds, terpenes, aliphatic alcohols, aldehydes, ke-
tones, acids and isoflavonoids. The principle constituents
from these compounds responsible for the antimicrobial ef-
fect include carvacrol, thymol, citral, eugenol and their pre-
cursors (Tiwari et al., 2011). The phenolic compounds are
the most abundant and important phytochemicals. They
exhibit antimicrobial, antioxidant, anti-allergic, anti-inflam-
matory and cardio-protective properties by acting as
reducing agents, hydrogen donors, oxygen quenchers and
metal chelators (Mariem et al., 2014).
The efficacy of EOs is dependant on factors such as the
chemical structure of their components, the concentration,
interactions with the food matrix, matching the antimicro-
bial spectrum of activity with the target microorganism(s)
and the method of application (Tiwari et al., 2011). The
combination of EOs with other natural antimicrobials or
even other chemical preservatives also shows positive
effects.
A large number of antimicrobial and antioxidant studies
on a variety of plant-derived compounds were performed
on fresh meat and fresh meat products, especially ground
meat and patties. These studies are summarized in excellent
reviews (Hygreeva, Pandey, & Radhakrishna, 2014;
Jayasena & Jo, 2013; Shah et al., 2014). The antimicrobials
and antioxidants mentioned in these reviews could also be
evaluated in fresh sausages. Other studies not listed by
these reviews include Capsicum annuum extract in minced
beef meat (Careaga et al., 2003), Ghardaq (Nitraria retusa)
extract in beef patties (Mariem et al., 2014), olive leaf,
blueberry and Zizyphus jujuba extracts in meatballs (G€
ok
& Bor, 2012) and makampom (Phyllanthus emblica L.)
extract in raw ground pork (Nanasombat et al., 2012).
The applications of plant-derived compounds in fresh
sausage studies are depicted in Table 4. A study on boere-
wors investigated the preservative effect of citrus seed
extract (Citrox). Although the shelf life increased, lipid
oxidation decreased and red colour loss was slower with
the addition of Citrox, the sensory attributes were nega-
tively affected (Van Schalkwyk, Hugo, Hugo, & Bothma,
2013). Laurus nobilis essential oil was evaluated in a fresh
Tuscan sausage stored at 7 C for 14 days (Da Silveira
et al., 2014). The shelf life increased and low levels of
rancidity were reported. Although the sensory characteris-
tics were affected, it was acceptable by consumers.
Plant-derived compounds may be used in conjunction
with lowered levels of chemical preservatives. In a study
on boerewors, rosemary in combination with chitosan and
lowered levels of SO
2
, increased the shelf life and red
colour of the product (Mathenjwa et al., 2012). A study
on Green tea and grape seed extract combined with low
levels of SO
2
in raw beef patties increased shelf life,
decreased lipid oxidation and decreased colour loss
(Ba~
n
on et al., 2007). The natural preservatives may also
be used in conjunction with different packaging materials.
In a study on reduced pork back-fat sausages using thymol
combined with modified atmosphere packaging (MAP), the
shelf life was extended (Table 4;Mastromatteo, Incoronato,
Conte, & Del Nobile, 2011).
Animal-derived compounds
Natural preservative compounds derived from animals
which have shown effectiveness in fresh meat and meat
18 C.J. Hugo, A. Hugo / Trends in Food Science & Technology 45 (2015) 12e23
products will be discussed in this section. Chitosan, lacto-
ferrin and lysozyme are the major animal-derived antimi-
crobials which will be discussed in this section. Since
studies on lactoferrin and lysozyme have not yet been per-
formed on fresh sausages, only the applications of chitosan
in fresh sausages are summarized in Table 5.
Chitosan
Chitosan is a deacetylated form of chitin and the second
most abundant biopolymer in the world after cellulose. It
consists of N-acetylglucosamine residues joined by
b(1e4) glycosidic links (Friedman & Juneja, 2011). It is
derived from the shell of crabs and shrimps and the cell
Table 4. Application of plant-derived natural preservatives in fresh sausages.
Preservative Activity against Product tested Quality attributes Reference
Garlic (fresh [F],
powder [P] or oil [O])
Aerobic plate count
(SR for F and P; NS for O)
Fresh chicken
sausage
Lipid oxidation Y, shelf life [Sallam et al. (2004)
Laurus nobilis
(bay leaf) essential oil
Psychrotrophic count (SR)
Total aerobic count (SR)
LAB count (SR)
Coliform count (SR)
Fresh Tuscan
sausage
Shelf life [, low oxidation levels,
sensory attributes affected but
still acceptable
Da Silveira et al. (2014)
Rosemary and ascorbic
acid mixture
Fresh pork
sausage
Red colour loss Y
Off-odour production Y
Mart
ınez, Cilla, Beltr
an,
and Roncal
es (2007)
Rosemary, chitosan
and SO
2
mixture
Total bacteria count (SR)
Yeast and mould count (SR)
Coliform count (NS)
Enterobacteriaceae count (NS)
Boerewors Shelf life [
Red colour [
Mathenjwa et al. (2012)
Origanum marjorana E. coli (w2 LR) Fresh sausage Shelf life [, sensory properties Y
with increased concentration
Busatta et al. (2008)
Citrus seed extract
(Citrox)
Total plate count (SR)
Coliform count (NS)
Yeast and mould count (SR)
Boerewors Shelf life [, lipid oxidation Y, red
colour loss Y, sensory properties Y
Van Schalkwyk et al. (2013)
Thymol combined
with MAP
Pseudomonas spp. (SR) Reduced pork
back-fat sausages
Shelf life [Mastromatteo et al. (2011)
LAB, lactic acid bacteria; ‘[’ and ‘Y’, increase and decrease; LR, log reduction; SR, significant reduction; NS, no significant reduction.
Table 5. Application of chitosan as an animal-derived natural preservative in fresh sausage products.
Preservative Activity against Product tested Quality attributes Reference
Chitosan Total bacterial and yeast and
mould counts (SR)
Coliform and Enterobacteriaceae
counts (NS)
Boerewors Shelf life [Mathenjwa et al. (2012)
Chitosan, rosemary
and SO
2
mixture
Total bacterial and yeast and mould
counts (SR)
Coliform and Enterobacteriaceae
counts (NS)
Boerewors Shelf life [
Red colour [
Mathenjwa et al. (2012)
Chitosan in 0.9% saline
at pH 6.2
Saccharomyces ludwigii (Inh)
Lactobacillus viridescens and
Listeria innocua (Ina)
Native microflora (1e3 LR)
Skinless pork
sausages
Shelf life [Sagoo, Board, and Roller (2002)
Chitosan and rosemary
extract combination
Fresh pork
sausages
Shelf life [
Lipid oxidation Y
Georgantelis et al. (2007)
Chitosan (0.5% and 1%
combined with nitrites
(150 ppm)
Lactic acid bacteria (SR)
Brochothrix thermosphacta (SR)
Enterobacteriaceae and
Pseudomonas (SR)
Yeasts and moulds (SR)
Fresh pork
sausages
Shelf life [
Lipid oxidation Y
Soultos, Tzikas, Abrahim, Georgantelis,
and Ambrosiadis (2008)
‘[’ and ‘Y’, increase and decrease; LR, log reduction; SR, significant reduction; NS, no significant reduction; Inh, inhibition; Ina, inactivation.
19C.J. Hugo, A. Hugo / Trends in Food Science & Technology 45 (2015) 12e23
wall of fungi (Gyawali & Ibrahim, 2014; Roller et al.,
2002). Although it is not generally regarded as a safe
(GRAS) compound, it is speculated that it will receive
GRAS status in the future (Zivanovic, Davis, & Golden,
2015).
Although chitosan exhibits antimicrobial activities
against a range of foodborne microorganisms
(Georgantelis, Ambrosiadis, Katikou, Blekas, &
Georgakis, 2007), it is more effective against Gram-
negative than Gram-positive bacteria (Friedman & Juneja,
2011). The antimicrobial and antioxidant activity of chito-
san are due to its ability to cause permeability of the cell
membranes, water-binding capacity and inhibition of
various enzymes (Coma, 2008; Georgantelis et al., 2007;
Helander, Nurmiaho-Lassila, Ahvenainen, Rhoades, & Rol-
ler, 2001; Kanatt, Chander, & Sharma, 2008).
Chitosan’s use as a food preservative has been limited
due to its insolubility at neutral and higher pH (Du, Zhao,
Dai, & Yang, 2009). However, a study by
Chantarasataporn et al. (2014) indicated that water-based
chitosan, in the forms of oligochitosan and nanowhisker
chitosan, significantly inhibited microbial activity and
extended the shelf life in raw minced pork meat (Table
5). Chitosan in combination with lowered levels of SO
2
and rosemary extract in a boerewors model system indi-
cated an increase in shelf life and red colour (Table 5;
Mathenjwa et al., 2012).
Lactoferrin
Lactoferrin (Lf) is an iron-binding glycoprotein isolated
from milk which has a wide range of antimicrobial activity
against bacteria (e.g., L. monocytogenes, E. coli, Klebsiella
and Carnobacterium) and viruses (Gyawali & Ibrahim,
2014). It has been approved in the USA for application in
meat products (Juneja et al., 2012; USDA-FSIS, 2010).
The mode of action is speculated to be either limiting mi-
crobial access to nutrients via iron chelation and/or destabi-
lizing the Gram-negative outer membrane (Gyawali &
Ibrahim, 2014).
A study on Turkish meatballs indicated that Lf and a
mixture of Lf and nisin increased the shelf life of the prod-
uct by significantly reducing the counts of the total aerobic
bacteria, coliforms, E. coli, total psychrophilic bacteria,
Pseudomonas spp. and yeasts and moulds (Colak,
Hampikyan, Bingol, & Aksu, 2008). No studies have
been performed on fresh sausages.
Lysozyme
Lysozyme is a bacteriolytic enzyme. It is isolated from
mammalian milk and avian eggs and has GRAS status for
direct addition to foods (FDA, 1998). According to Juneja
et al. (2012) the white lysozyme from eggs has bacteriolytic
activity due to the hydrolysis of the b-1,4 linkage between
the N-acetylmuramic acid and N-acetyl-glucosamine in the
peptidoglycan of the Gram-positive microbial cell wall.
Lysozyme has better effectivity against Gram-negative
bacteria when used in combination with detergents and che-
lators (e.g. EDTA), nisin and lactoferrin (Branen &
Davidson, 2004). Lysozyme is widely reported for its appli-
cation as a preservative for meat, meat products, fish, fish
products, milk and dairy products, and fruits and vegetables
(Gyawali & Ibrahim, 2014). However, literature is not
available on its use in fresh sausages.
In a study on minced meat using a combination of chito-
san and lysozyme, the shelf life of the product was increased
by inhibiting the growth of B. cereus,E. coli and Pseudo-
monas fluorescens while a significant reduction was noticed
in the Staph. aureus counts. This combination also decreased
lipid oxidation (Rao, Chander, & Sharma, 2008).
The combination of lysozyme with nisin and EDTA was
evaluated in ostrich patties. L. monocytogenes was signifi-
cantly reduced, the total viable count and lactic acid bacte-
ria count decreased by 1 log and 2 log, respectively, while
Enterobacteriaceae and Pseudomonas were not affected.
Shelf life therefore increased, the colour of the product
was not affected while off-odours developed
(Mastromatteo, Lucera, Sinigaglia, & Corbo, 2010). A
lysozyme and nisin mixture also showed inhibition of B.
thermosphacta and a significant reduction of Carnobacte-
rium spp. in cores of lean and fat pork tissue (Nattress,
Yost, & Baker, 2001).
Possible other natural preservatives
Research on a few other natural preservatives has only
been evaluated in vitro, and has not yet been tested in
food preservation and/or applied in food systems. These
preservatives may find applications in fresh sausage preser-
vation in future. An example includes algae and mush-
rooms which have been reported to have antimicrobial,
antiviral, antioxidant, antifouling, anti-inflammatory, cyto-
toxic, antimitotic activities (references cited in Gyawali &
Ibrahim, 2014). Saponins are naturally occurring glycosides
in some plants which showed promising results as a broad-
spectrum antimicrobial (Juneja et al., 2012). Flavonoids are
bioactive pigment compounds in some plant parts and
showed broad-spectrum antimicrobial activities as well as
an antifungal preservative (Juneja et al., 2012).
Conclusions
Microbial-, plant- and animal-derived natural com-
pounds were investigated for their antimicrobial, antioxi-
dant and antibrowning properties in fresh sausages.
Lacticin and reuterin as bacteriocins and citric acid,
sodium lactate and sodium acetate as organic acids pro-
duced by microorganisms, have been evaluated in fresh
sausages and showed antimicrobial activity against Gram-
positive and Gram-negative pathogens.
The plant-derived compounds have been investigated
extensively since a vast range of these compounds show
excellent antimicrobial, antioxidant and anti-browning ac-
tivities in meat products and fresh sausages. Chitosan is
the only animal-derived antimicrobial that has yet been
20 C.J. Hugo, A. Hugo / Trends in Food Science & Technology 45 (2015) 12e23
evaluated in fresh sausages and showed increased shelf life
of these products.
It was evident that combinations of the natural antimi-
crobials with either other natural antimicrobials, or lowered
levels of synthetic/chemical antimicrobials, or with other
hurdles, such as specific packaging material, will enhance
the performance of all three types of antimicrobials dis-
cussed in this review.
A vast range of research has been performed on meat
and meat products. Many studies are however, in vitro
studies and need to be evaluated in food systems since com-
plex food matrices such as fresh sausages, may have an ef-
fect on the activity of the natural preservative. Also,
sensory studies should always form part of these studies
to ascertain consumer’s perception.
References
Al-Sheddy, I., Al-Dagal, M., & Bazaraa, W. A. (1999). Microbial and
sensory quality of fresh camel meat treated with organic acid salts
and/or bifidobacteria. Journal of Food Science, 64, 336e339.
Alvarez-Ord
o~
nez, A., Fern
andez, A., Bernardo, A., & L
opez, M.
(2010). Acid tolerance in Salmonella typhimurium induced by
culturing in the presence of organic acids at different growth
temperatures. Food Microbiology, 27,44e49.
Ayachi, B. E., Daoudi, A., & Benkerroum, N. (2007). Effectiveness of
commercial organic acids’ mixture (AcetolacÔ) to extend the shelf
life and enhance the microbiological quality of Merguez sausages.
American Journal of Food Technolology, 2, 190e195.
Balentine, C. W., Crandall, P. G., O’Bryan, C. A., Duong, D. Q., &
Pohlman, F. W. (2006). The pre- and post-grinding application of
rosemary and its effects on lipid oxidation and colour during
storage of ground beef. Meat Science, 73, 413e421.
Ba~
n
on, S., D
ıaz, P., Rodr
ıguez, M., Garrido, M. D., & Price, A. (2007).
Ascorbate, green tea and grape seed extracts increase the shelf-life
of low sulphite beef patties. Meat Science, 77, 626e633.
Branen, J. K., & Davidson, P. M. (2004). Enhancement of nisin,
lysozyme and monolaurin antimicrobial activities by
ethylenediaminetetraacetic acid and lactoferrin. Journal of Food
Microbiology, 90,63e74.
Busatta, C., Vidal, R. S., Popiolski, A. S., Mossi, A. J., Dariva, C.,
Rodrigues, M. R. A., et al. (2008). Application of Origanum
majorana L. essential oil as an antimicrobial agent in sausage.
Food Microbiology, 25, 207e211.
Cannon, J. E., Morgan, J. B., Heavner, J., McKeith, F. K., Smith, G. C.,
& Meeker, D. L. (1995). Pork quality audit: a review of the factors
influencing pork quality. Journal of Muscle Foods, 6, 369e402.
Careaga, M., Fern
andez, E., Dorantes, L., Mota, L., Jaramillo, M. E., &
Hernandez-Sancheza, H. (2003). Antibacterial activity of
Capsicum extract against Salmonella typhimurium and
Pseudomonas aeruginosa inoculated in raw beef meat.
International Journal of Food Microbiology, 83, 331e335.
Carr, J. G., Davies, P. A., & Sparks, A. H. (1976). The toxicity of
sulphur dioxide towards certain lactic acid bacteria from
fermented apple juice. Journal of Applied Bacteriology, 40,
201e212.
Chantarasataporn, P., Tepkasikul, P., Kingcha, Y., Yoksan, R.,
Pichyangkura, R., Visessanguan, W., et al. (2014). Water-based
oligochitosan and nanowhisker chitosan as potential food
preservatives for shelf-life extension of minced pork. Food
Chemistry, 159, 463e470.
Cocolin, L., Rantsiou, K., Iacumin, L., Urso, R., Cantoni, C., &
Comi, G. (2004). Study of the ecology of fresh sausages and
characterization of populations of lactic acid bacteria by
molecular methods. Applied and Environmental Microbiology, 70,
1883e1894.
Colak, H., Hampikyan, H., Bingol, E. B., & Aksu, H. (2008). The effect
of nisin and bovine lactoferrin on the microbiological quality of
Turkish-style meatball (tekirda
gk
€
ofte). Journal of Food Safety, 28,
355e375.
Coma, V. (2008). Bioactive packaging technologies for extended shelf
life of meat-based products. Meat Science, 78,90e103.
Crist, C. A., Williams, J. B., Schilling, M. W., Hood, A. F., Smith, B. S.,
& Campano, S. G. (2014). Impact of sodium lactate and vinegar
derivates on the quality of fresh Italian pork sausage links. Meat
Science, 96, 1509e1516.
Crowley, H., Cagney, C., Sheridan, J. J., Anderson, W.,
McDowell, D. A., Blair, I. S., et al. (2005). Enterobacteriaceae in
beef products from retail outlets in the Republic of Ireland and
comparison of the presence and counts of E. coli O157:H7 in
these products. Food Microbiology, 22, 409e414.
Dalton, H. K., Board, R. G., & Davenport, R. R. (1984). The yeasts of
British fresh sausage and minced beef. Antonie van Leeuwenhoek,
50, 227e248.
Da Silveira, S. M., Luciano, F. B., Fronza, N., Cunha, A., Jr.,
Scheuermann, G. N., et al. (2014). Chemical composition and
antibacterial activity of Laurus nobilis essential oil towards
foodborne pathogens and its application in fresh Tuscan sausage
stored at 7 C. LWT eFood Science and Technology, 59,86e93.
Davies, E. A., Milne, C. F., Bevis, H. E., Potter, R. W., Harris, J. M.,
Williams, G. C., et al. (1999). Effective use of nisin to control lactic
acid bacterial spoilage in vacuum-packed bologna-type sausage.
Journal of Food Protection, 62, 1004e1010.
Dillon, V. M., & Board, R. G. (1994). Future prospects for natural
antimicrobial food preservation systems. In V. M. Dillon, &
R. G. Board (Eds.), Natural antimicrobial systems and food
preservation (pp. 297e303). Wallingford: CAB International.
Du, Y., Zhao, Y., Dai, S., & Yang, B. (2009). Preparation of water-
soluble chitosan from shrimp shell and its antibacterial activity.
Innovative Food Science and Emerging Technologies, 10,
103e107.
Dyett, E. J., & Shelley, D. (1966). The effects of sulphite preservative in
British fresh sausages. Journal of Applied Bacteriology, 29,
439e446.
Eisel, W. G., Linton, R. H., & Muriana, P. M. (1997). A survey of
microbial levels for incoming raw beef, environmental sources,
and ground beef in a red meat processing plant. Food
Microbiology, 14, 273e282.
El-Ziney, M., van den Tempel, T., Debevere, J., & Jakobsen, M. (1999).
Application of reuterin produced by Lactobacillus reuteri 12002
for meat decontamination and preservation. Journal of Food
Protection, 62, 257e261.
Fallico, V., McAuliffe, O., Ross, R. P., Fitzgerald, G. F., & Hill, C.
(2011). The potential of lacticin 3147, enterocin AS-48, lacticin
481, variacin and sakacin P for food biopreservation. In C. Lacroix
(Ed.), Protective cultures, antimicrobial metabolites and
bacteriophages for food and beverage biopreservation (pp.
100e128). Cambridge, UK: Woodhead Publishing Limited.
Farber, J. M., Malcolm, S. A., Weiss, K. F., & Johnston, M. A. (1988).
Microbiological quality of fresh and frozen breakfast type sausages
sold in Canada. Journal of Food Protection, 51, 397e404.
FDA. (1998). Direct food substances affirmed as generally recognized
as safe: egg white lysozyme. Federal Register, 63, 12421e12426.
FDA. (2014). CFR eCode of Federal Regulations Title 21, Part 182-
Substances generally recognized as safe. Sec. 182.20 eEssential
oils, oleoresins (solvent-free), and natural extractives (including
distillates). Silver Spring, MD: FDA.
Friedman, M., & Juneja, V. K. (2011). Benficial applications of
chitosans. In M. Rai, & M. Chikindas (Eds.), Natural antimicrobials
in food safety and quality (pp. 131e153). Oxfordshire, UK: CAB
International.
21C.J. Hugo, A. Hugo / Trends in Food Science & Technology 45 (2015) 12e23
G
alvez, A., Abriouel, H., Lucas, R., Jos
e, M., & Burgos, G. (2011).
Bacteriocins for bioprotection of foods. In M. Rai, & M. Chikindas
(Eds.), Natural antimicrobials in food safety and quality (pp.
39e61). Oxfordshire, UK: CAB International.
Georgantelis, D., Ambrosiadis, I., Katikou, P., Blekas, G., &
Georgakis, S. A. (2007). Effect of rosemary extract, chitosan and a-
tocopherol on microbiological parameters and lipid oxidation of
fresh pork sausages stored at 4 C. Meat Science, 76, 172e181.
G€
ok, V., & Bor, Y. (2012). Effect of olive leaf, blueberry and Zizyphus
jujuba extracts on the quality and shelf life of meatball during
storage. Journal of Food, Agriculture and Environment, 10,
190e195.
Gould, G. W., & Russell, N. J. (2003). Sulfite. In G. W. Gould, &
N. J. Russel (Eds.), Food preservatives (2nd ed.). (pp. 85e93). New
York: Kluwer Academic/Plenum Plublisher.
Gunnison, A. F., Jacobsen, D. W., & Schwartz, H. J. (1987). Sulfite
hypersensitivity. A critical review. Crititical Reviews in Toxicology,
17, 186e214.
Gyawali, R., & Ibrahim, S. A. (2014). Natural products as
antimicrobial agents. Food Control, 46, 412e429.
Harper, D. (2001e2014). The online etymology dictionary.http://
www.etymonline.com/index.php?allowed_in_
frame¼0&search¼sausage&searchmode¼nl Retrieved on 06/11/
2014.
Helander, I. M., Nurmiaho-Lassila, E.-L., Ahvenainen, R., Rhoades, J.,
& Roller, S. (2001). Chitosan disrupts the barrier properties of the
outer membrane of gram-negative bacteria. International Journal
of Food Microbiology, 71, 235e244.
Huffman, R. D. (2002). Current and future technologies for the
decontamination of carcasses and fresh meat. Meat Science, 62,
285e294.
Hussain, I., Mahmood, M. S., Akhtar, M., & Khan, A. (2007).
Prevalence of Campylobacter species in meat, milk and other food
commodities in Pakistan. Food Microbiology, 24, 219e222.
Hygreeva, D., Pandey, M. C., & Radhakrishna, K. (2014). Potential
applications of plant based derivatives as fat replacers,
antioxidants and antimicrobials in fresh and processed meat
products. Meat Science, 98,47e57.
Jayasena, D. D., & Jo, C. (2013). Essential oils as potential
antimicrobial agents in meat and meat products: a review. Trends
in Food Science and Technology, 34,96e108.
Juneja, V. K., Dwivedi, H. P., & Yan, X. (2012). Novel natural food
antimicrobials. Annual Reviews in Food Science and Technology,
3, 381e403.
Kanatt, S. R., Chander, R., & Sharma, A. (2008). Chitosan and mint
mixture: a new preservative for meat and meat products. Food
Chemistry, 107, 845e852.
Kim, S.-J., Cho, A. R., & Han, J. (2013). Antioxidant and antimicrobial
activities of leafy green vegetable extracts and their application to
meat product preservation. Food Control, 29, 112e120.
Kuleas
¸an, H., & Cakmakc
¸i, M. L. (2002). Effect of reuterin produced
by Lactobacillus reuteri on the surface of sausages to inhibit the
growth of Listeria monocytogenes and Salmonella spp. Nahrung/
Food, 46, 408e410.
Langa, S., Landete, J. M., Mart
ın-Cabrejas, I., Rodr
ıguez, E.,
Argu
es, J. L., & Medina, M. (2013). In situ reuterin production by
Lactobacillus reuteri in dairy products. Food Control, 33,
200e206.
Little, C. L., Richardson, J. F., Owen, R. J., de Pinna, E., &
Threlfall, E. J. (2008). Campylobacter and Salmonella in raw red
meats in the United Kingdom: prevalence, characterization and
antimicrobial resistance pattern, 2003 e2005. Food
Microbiology, 25, 538e543.
Liu, F., Yang, R.-Q., & Li, Y. F. (2006). Correlations between growth
parameters of spoilage micro-organisms and shelf-life of pork
stored under air and modified atmosphere at 2, 4 and 10 C.
Food Microbiology, 23, 578e581.
Lucera, A., Costa, C., Conte, A., & D. Nobile, M. A. (2012). Food
applications of natural antimicrobial compounds. Frontiers in
Microbiology, 3, 287. http://dx.doi.org/10.3389/
fmicb.2012.00287.
Mani-L
opez, E., Garc
ıa, H. S., & L
opez-Malo, A. (2012). Organic
acids as antimicrobials to control Salmonella in meat and poultry
products. Food Research International, 45, 713e721.
Mariem, C., Sameh, M., Nadhem, S., Soumaya, Z., Najiba, Z., &
Raoudha, E. G. (2014). Antioxidant and antimicrobial properties of
the extracts from Nitraria retusa fruits and their applications to
meat product preservation. Industrial Crops and Products, 55,
295e303.
Mart
ınez, L., Cilla, I., Beltr
an, J. A., & Roncal
es, P. (2007). Effect of
illumination on the display life of fresh pork sausages packaged in
modified atmosphere. Influence of the addition of rosemary,
ascorbic acid and black pepper. Meat Science, 75, 443e450.
Mastromatteo, M., Incoronato, A. L., Conte, A., & D. Nobile, M. A.
(2011). Shelf life of reduced pork back-fat content sausages as
affected by antimicrobial compounds and modified atmosphere
packaging. International Journal of Food Microbiology, 150,1e7.
Mastromatteo, M., Lucera, A., Sinigaglia, M., & Corbo, M. R. (2010).
Synergic antimicrobial activity of lysozyme, nisin, and EDTA
against Listeria monocytogenes in ostrich meat patties. Journal of
Food Science, 75, 422e429.
Mathenjwa, S. A., Hugo, C. J., Bothma, C., & Hugo, A. (2012). Effect
of alternative preservatives on the microbial quality, lipid stability
and sensory evaluation of boerewors. Meat Science, 91, 165e172.
Mrema, N., Mpuchane, S., & Gashe, B. A. (2006). Prevalence of
Salmonella in raw minced meat, raw fresh sausages and raw
burger patties from retail outlets in Gaborone, Botswana. Food
Control, 17, 207e212.
Nanasombat, S., Khanha, K., Phan-im, J., Jitaied, J.,
Wannasomboon, S., Patradisakorn, S., et al. (2012). Antimicrobial
and antioxidant activities of Thai local fruit extracts: application of
selected fruit extract, Phyllantus emblica Linn. as a natural
preservative in raw ground pork during refrigerated storage.
Online Journal of Science and Technology, 2,1.
Nattress, F. M., Yost, C. K., & Baker, L. P. (2001). Evaluation of the
ability of lysozyme and nisin to control meat spoilage bacteria.
International Journal of Food Microbiology, 70, 111e119.
Nortj
e, G. L., Vorster, S. M., Greebe, R. P., & Steyn, P. L. (1999).
Occurrence of Bacillus cereus and Yersinia enterocolitica in South
African retail meats. Food Microbiology, 16, 213e217.
Olofsson, T. C., Ahrn
e, S., & Molin, G. (2007). Composition of the
bacterial population of refrigerated beef, identified with direct 16S
rRNA gene analysis and pure culture technique. International
Journal of Food Microbiology, 118, 233e240.
Oussalah, M., Callet, S., Saucier, L., & Lacroix, M. (2007). Inhibitory
effects of selected plant essential oils on the growth of four
pathogenic bacteria: E. coli O157:H7, Salmonella Typhimurium,
Staphylococcus aureus and Listeria monocytogenes.Food Control,
18, 414e420.
Rajendran, K., Nagappan, R., & Ramamurthy, K. (2013). Short
communication. A study on the bactericidal effect of nisin purified
from Lactococcus lactis.Ethiopian Journal of Biological Sciences,
10,95e102.
Raju, C. V., Shamasundar, B. A., & Udupa, K. S. (2003). The use of
nisin as a preservative in fish sausage stored at ambient (28 2C)
and refrigerated (6 2C) temperatures. International Journal of
Food Science and Technology, 38, 171e185.
Rao, M. S., Chander, R., & Sharma, A. (2008). Synergistic effect of
chitooligosaccharides and lysozyme for meat preservation.
Lebensmittel-Wissenschaft und-Technologie, 41, 1995e2001.
Roller, S., Sagoo, S., Board, R., O’Mahony, T., Caplice, E.,
Fitzgerald, G., et al. (2002). Novel combinations of chitosan,
carnocin and sulphite for the preservation of chilled pork sausages.
Meat Science, 62, 165e177.
22 C.J. Hugo, A. Hugo / Trends in Food Science & Technology 45 (2015) 12e23
Romans, J. R., William, J. C., Carloson, C. W., Greaser, M. L., &
Jones, K. W. (2001). The meat we eat (4th ed.). Danville: Interstate
Publishers, Inc.
Russo, F., Ercolini, D., Mauriello, G., & Villani, F. (2006). Behaviour of
Brochothrix thermosphacta in presence of other meat spoilage
microbial groups. Food Microbiology, 23, 797e802.
Rust, R. E. (1987). Sausage products. In J. F. Price, & B. S. Schweigert
(Eds.), The science of meat and meat products (3rd ed.). (pp.
457e486). Westport: Connecticut, USA: Food & Nutrition Press,
Inc.
Sachindra, N. M., Sakhare, P. Z., Yashoda, K. P., & Rao, D. N. (2005).
Microbial profile of buffalo sausage during processing and storage.
Food Control, 16,31e35.
Sagoo, S., Board, R., & Roller, S. (2002). Chitosan inhibits growth of
spoilage micro-organisms in chilled pork products. Food
Microbiology, 19, 175e182.
Sallam, Kh I., Ishioroshi, M., & Samejima, K. (2004). Antioxidant and
antimicrobial effects of garlic in chicken sausage. Lebensmittel
Wissenschraft und-Technologie, 37, 849e855.
Savic, I. V. (1985). Small-scale sausage production. Rome, Italy:
Publications Division, Food and Agriculture Organization of the
United Nations.
Scannell, A. G. M., Hill, C., Buckley, D. J., & Arendt, E. K. (1997).
Determination of the influence of organic acids and nisin on shelf-
life and microbiological safety aspects of fresh pork sausage.
Journal of Applied Microbiology, 83, 407e412.
Scannell, A. G. M., Ross, R. P., Hill, C., & Arendt, E. K. (2000). An
effective lacticin biopreservative in fresh pork sausage. Journal of
Food Protection, 63, 370e375.
Shah, M. A., Bosco, S. J. D., & Mir, S. A. (2014). Plant extracts as
natural antioxidants in meat and meat products. Meat Science, 98,
21e33.
Siragusa, G. R., Cutter, C. N., & Willett, J. L. (1999). Incorporation of
bacteriocin in plastic retains activity and inhibits surface growth of
bacteria on meat. Food Microbiology, 16, 229e235.
Soultos, N., Tzikas, Z., Abrahim, A., Georgantelis, D., &
Ambrosiadis, I. (2008). Chitosan effects on quality properties of
Greek style fresh pork sausages. Meat Science, 80, 1150e1156.
Sultana, T., Rana, J., Chakraborty, S. R., Das, K. K., Rahman, T., &
Noor, R. (2014). Microbiological analysis of common
preservatives used in food items and demonstration of their in vitro
anti-bacterial activity. Asian Pacific Journal of Tropical Diseases,
4, 452e456.
Sun, Y., Li, Y., Song, H., & Zhu, Y. (2011). Microbial fermentation for
food preservation. In M. Rai, & M. Chikindas (Eds.), Natural
antimicrobials in food safety and quality (pp. 77e94). Oxfordshire,
UK: CAB International.
Thomas, R., Anjaneyulu, A. S. R., & Kondaiah, N. (2008).
Development of shelf stable pork sausages using hurdle
technology and quality at ambient temperature (37 C1C)
storage. Meat Science, 79,1e12.
Tiwari, B. K., Valdramis, V. P., Bourke, P., & Cullen, P. (2011).
Application of plant-based antimicrobials in food preservation. In
M. Rai, & M. Chikindas (Eds.), Natural antimicrobials in food
safety and quality (pp. 204e223). Oxfordshire, UK: CAB
International.
USDA-FSIS. (2010). Safe and suitable ingredients used in the
production of meat, poultry, and egg products. FSIS Directive
7120.1.
USDA-FSIS. (1999). Safe practices for sausage production. Distance
learning course manual. http://www.waltonsinc.com/PDF/
SausageFSIS.pdf Accessed 04.11.14..
USDA-FSIS. (2014). Sausages and food safety.http://www.fsis.usda.
gov/wps/portal/fsis/topics/food-safety-education/get-answers/food-
safety-fact-sheets/meat-preparation/sausages-and-food-safety/ct_
index Accessed 04.11.14.
Van Schalkwyk, C. P. B., Hugo, A., Hugo, C. J., & Bothma, C. (2013).
Evaluation of a natural preservative in a boerewors model system.
Journal of Food Processing and Preservation, 37, 824e834.
Varnam, A. H., & Sutherland, J. P. (1995). Meat and meat products.
London: Chapman & Hall.
Vorster, S. M., Greebe, R. P., & Nortj
e, G. L. (1994). Incidence of
Staphylococcus aureus and Escherichia coli in ground beef,
broilers and processed meats in Pretoria, South Africa. Journal of
Food Protection, 57, 305e310.
Zhang, H., Kong, B., Xiong, Y. L., & Sun, X. (2009). Antimicrobial
activities of spice extracts against pathogenic and spoilage
bacteria in modified atmosphere packaged fresh pork and vacuum
packaged ham slices stored at 4 C. Meat Science, 81, 686e692.
Zhang, S., & Mustapha, A. (1999). Reduction of Listeria
monocytogenes and Escherichia coli O157:H7 numbers on
vacuum-packaged fresh beef treated with nisin or nisin combined
with EDTA. Journal of Food Protection, 62, 1123e1127.
Zhou, G. H., Xu, X. L., & Liu, Y. (2010). Preservation technologies for
fresh meat eA review. Meat Science, 86, 119e128.
Zivanovic, S., Davis, R. H., & Golden, D. A. (2015). Chitosan as an
antimicrobial in food products. In T. M. Taylor (Ed.), Handbook of
natural antimicrobials for food safety and quality (pp. 153e182).
Cambridge, UK: Woodhead Publishing.
23C.J. Hugo, A. Hugo / Trends in Food Science & Technology 45 (2015) 12e23
