Site Loader
Rock Street, San Francisco

Title:
The Use of Bacteria in Food Industry

1.    Introduction

We Will Write a Custom Essay Specifically
For You For Only $13.90/page!


order now

The microbes that are
important in food grouped into several species and types of bacteria, yeasts,
molds and viruses. Bacteria, yeasts, molds and viruses are important in food as
it involved in many types of processes which include in the food industry. The
bacteria are used in food industry for fermentation, as a probiotic for human
consumption, as the main reason for food spoilage and the main factor
contribute to foodborne disease. The fermentation of food using bacteria
involves many processes for producing many different types of food. The
examples of food that are fermented by the bacteria are the dairy product
(milk), cheese, alcohol, vegetable and fruits (Sansonetti, Curcio, Calabro
& Lorio,2009). Probiotics are “living micro-organism, which gives benefit
in human health above the basic nutrient which mainly comes from Lactic Acid
Bacteria (LAB) (Ljungh & Wadstrom, 2006). The LAB and other types of
microbes are also used as a bio-preservatives as it produces a bactericidin
which can kill and inhibit the growth of the bacteria that can cause the
spoilage in the food (Abee, Krockel & Hill, 1995). The main contaminants
that can be found in the paper for food packaging are Bacillus sp. and
Paenibacillus sp which will produce an enzyme which will initiate food
spoilage. (Suominen, Suihko &Salkinoja-Salonen,1997) while Enterobacter sp.
is mainly the bacteria that involve in contaminating most of the food which can
cause foodborne disease. (Ray, 2005).

Foods are dynamic systems in
which its changes occur in pH, atmosphere, nutrient composition and microflora
over time. Each food product has its own unique flora, determined by the raw
materials used, food processing parameters and subsequent storage conditions
Microbial food spoilage is an area of global concern as it has been estimated
that as much as 25% of all food produced is lost post-harvest owing to
microbial activity (Gram & Dalgard, 2002). So, understanding the sources of
microorganism in food is important to develop methods to control access of some
microorganism in the food, develop processing methods to kill them in food, and
determine the microbiological quality of food, as well as set up
microbiological standards and specifications of foods and food ingredients
(Ray, 2005).

1.    Fermentation
of food using bacteria

The fermentation of food
using bacteria involves many processes for producing many different types of
food. The examples of food that are fermented by the bacteria are a dairy
product (milk), cheese, alcohol, vegetable and fruits. The fermentation of milk
for producing cheese also can develop cheese whey by-product which can be
further fermented forming bio-ethanol as bio-fuels (Sansonetti, Curcio, Calabro
& Lorio,2009) and produce ruminant feed supplement which is rich in crude
protein (Reddy, Henderson & Erdman,1976).

Dairy industry plays a
significant part in the food producing industry and for production of the
ethanol. A by-product of the cheese manufacturing process which is cheese whey,
with a major component of lactose, proteins, lipids and mineral salts forms a
cheap and nutrient-rich material for producing other types of compound
(Dragone, Musatto, Silva & Teixeira, 2011). The bioethanol also can be
produced from fermentation of cheese whey by-product and vegetable biomasses,
such as sugar cane and cereals. Based on the research done, the lactose
fermentation of Kluyveromyces marxianus with crude whey forms a low yield which
only 11% production in 22 hours but still achieved (Sansonetti, Curcio, Calabro
& Lorio,2009).

Low ethanol yields can be
obtained due to low lactose content of either raw or ultrafiltered cheese whey
through fermentation. Fermentation of cheese whey to ethanol of pure culture of
K. marxianus (DSMZ 7239) can be done using five cycle repeated fed-batch
operations (Ozmihzi & Kargi,2007). Cheese whey also can undergo bacterial
fermentation producing ruminant feed supplement that is rich in crude protein.
The steps only require the fermentation which forming lactic acid by
Lactobacillus bulgaris at 43°C and pH 5.5(Reddy, Henderson & Erdman,1976).

Several Nigerian and West
African foods also undergo fermentation and are used as a food colouring or
preservative. The main objectives of fermentation are to enhance the flavour
and the quality. During fermentation, changes in both desirable and undesirable
may occur in the food material. Fermentation in most cases resulted in better
quality food material both in terms of contents of nutrients and toxic
substances. (Abu, Zaria & Nigeria, 1979). Yeast plays an important role in
fermentation processes. However, according to Ozmihci and Kargi (2007), not all
yeast strains can ferment lactose to ethanol. For instance, the Saccharomyces
sp. have less galactose fermenting enzymes which makes them unable to ferment
lactose to ethanol.

2.    Probiotics

Probiotics are “living
micro-organism, which gives benefit in human health above the basic nutrient.
Lactic Acid Bacteria(LAB) are mostly the probiotic microbes exist. The example
of the LAB is Lactobacillus sp, Bifidobacterium sp and Enterococcus sp. Saccharomyces
boulardii yeast and Bacillus sp, Clostridium butyricum bacteria also can be
processed to form probiotic. However, the use of probiotic-derived from
Enterococcus sp. is in doubt due to the safety feature in terms of transfer of
the genes conferring the antibiotic resistance. Scientists have made an
agreement that the ability to survive through the environment of gastric acid,
bile and pancreatic juice exposure, and exert a favourable effect in the lower
small intestine and colon, own by the probiotic. The great effect can be
achieved when the colonisation of the microbes in the intestinal surface mucus
layer occur as it can affect the intestinal immune system, change enteric
pathogens, supply antioxidants and antimutagens, and another effect that is possible
by cell signalling (Ljungh & Wadstrom, 2006).

Starter Lactic Acid Bacteria
(SLAB) terms are applied to characterise bacterial strains that able to grow in
the selective environment of dairy production. Its includes a combination of
Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus.  Although L. delbrueckii ssp. bulgaricus was
investigated to survive the gastric transit, it is not native to humans in
dissimilarity to almost all probiotic bacteria for human ingestion. As results,
the L. delbrueckii ssp. bulgaricus in most products has been changed by or
mixed with well-known probiotics such as Lactobacillus acidophilus,
Lactobacillus casei and Lactobacillus rhamnosus, which are always there in the
human gastro-urogenital, to increase yoghurt’s health value. Generally, the
selection character for starter cultures is their rate of acidification and
flavour-producing characteristics (Velez et.al, 2007).

The use of antibiotics such
as oxytetracycline has been prohibited by several countries due to serious
environmental hazards and some carcinogenic effects in many. Besides, the use
of antibiotics has become limited because certain pathogens have developed
resistance to the drugs. , lactic acid bacteria are commonly used as probiotic
in animal nutrition which are Lactobacillus bulgaricus, L. acidophilus, L.
sporogenes, L. casei, L. plantarum, and Streptococcus thermophillus .The
beneficial effects of these probiotics include higher growth and feed
efficiency, prevention of intestinal disorders and pre pre-digestion of
anti-nutritional factors present in the ingredients. (Suzer et.al,2008).

3.    Food
preservation, storage and spoilage

Dynamic systems of the foods
make changes in pH, atmosphere, the composition of the nutrient and microflora
per time. The unique flora of each food can be determined by using crude
materials, the food processing guideline and consecutive storage status. The
microflora will change due to differences in the ability of the microbes to
adapt the preservation condition during the storage (Gram & Dalgard, 2002).

The LAB is used as a
bio-preservatives as it produces a bactericidin which can kill and inhibit the
growth of the bacteria that can cause the spoilage in the food. Lantibiotics,
small heat-stable peptides, large labile proteins and complex protein are four major
classes of bacteriocins produced. Its process needs the association of the
carbohydrates and lipids components. Salmonella sp. and other Gram-negative
bacteria become susceptible to nisin after being exposed to treatments that
adjust the permeability boundary character of the outer membrane. Protective
cultures in a various type of food products can be applied by the
bacteriocin-producing strains. For instance, enough characterization,
homofermentative, mildly acidifying, bacteriocinogenic LAB is the best for
bio-preservation of meats where adjustment of the meats is undesirable (Abee,
Krockel & Hill, 1995).

LAB genera that are always
turn up on vacuum or adjusted atmosphere packaged meat are Lactobacillus,
Leuconostoc and Camobacterium. The most used process in marketing of meat is
vacuum packaging for distribution and continued storage followed by meat
removal from packaging for the preparation of the retail cuts. The oxygenic
permeable film is used for displaying the retail cuts meat, followed by refrigeration
of the cabinet to facilitate buyers selection.LAB may involve in producing an
unneeded sensory adjustment of meat during the aerobic storage process.
However, the LAB objectives of using these strain or their bacteriocins are for
the extension of the storage life for the chilled meats (Leisner, Greer, Dilts
& Stiles, 1995)

The main contaminants that
can be found in the paper for food packaging are Bacillus sp. and Paenibacillus
sp. These genera produce enzyme such as amylase and caseinase that initiate
food spoilage. A low number of bacteria found in the aseptic food also should
take account as the bacteria can migrate across the packaging to the food
product when the temperature is favourable and been left for a long time.
(Suominen, Suihko -Salonen,1997)

High nutrient and a moisture
concentration of the food processing environment favour the growth of
surface-associated microbes and their polymers; biofilm. Resistance to regulate
strategies and biocides is features of the biofilm that help in faster
re-growth. Many spoilage microbes always generated together in the complex
(Korber, Mangalappalli-lllathu, Vidovic, 2009).

The example of bacteria that
can cause spoilage to the fish is fermentative bacteria such as Vibrionaceae,
and gram-negative bacteria like Pseudomonas spp. and Shewanella spp. These
bacteria growth can be inhibited by CO2 packing and prefer Photobacterium
phosphoreum and lactic acid bacteria (LAB) with an addition of a small level of
NaCl, a little acidification and cold storage in vacuum-pack. The acidification
or addition of the preservatives such as sorbate and benzoate which increase
the preservation pressure as in semi pressed seafood gives the lactobacilli and
yeast the ability to grow (Gram & Dalgard, 2002).

4.    Foodborne
disease bacteria

The crude and processed food
consist of a much different variety of molds, yeast, bacteria and viruses
though the internal tissue of a healthy plant is sterile. The microbes can grow
in the product from a natural source (internal) and external sources of which food
comes into contact in the time of production to the time of consumption. Other
than natural microbes, microbes from outside sources such as air, soil, sewage,
water, feeds, humans, food ingredients, equipment, packages and insect can also
cause a food contamination. The types of microbes to their levels of the source
to contaminate the food diverge widely and depending on the degree of
sanitation that is used when handling the foods.

Enterobacter is mainly the
bacteria that involve in contaminating most of the food. Enteric types of the
pathogens can be found in the soil that is contaminated with untreated sewage.
Animal and birds which consumed by the human also normally have the indigenous
microbes in their digestive, respiratory, respiratory and urinogenital tracts,
the teat canal in the udder as well as the skin, hooves, hair and feathers.
Pathogens such as Salmonella serovars, pathogenic Escherichia coli,
Campylobacter jejuni, Yersinia enterocolitica and Listeria monocytogenes can
present in the animal as carriers without showing symptoms (Ray, 2005).

However, based on the
research done by Munda, Zakour & Worobo (2004), the growth of foodborne
disease bacteria can be inhibited by using crude honey effectively by in vitro
procedure against wound-infecting bacteria which includes Escherichia coli,
Staphylococcus aureus, and Salmonella enterica Ser. Typhimurium. In thousand
years, the crude honey has been used as a topical and gastrointestinal antidote
and have been recognized in the medical field. The acidity, osmolarity and
enzymatic generation of hydrogen peroxide via glucose oxidase of the additional
honey component such as aromatic acid or phenolic compound also involve in
overall antimicrobial activity (Munda, Zakour & Worobo, 2004).

5.    Current
research

Based on the results the
latest research that has been done, the growth of food-borne and spoilage
microbes can be prevented using essential oil or organic extract of-of L.
japonica as natural antimicrobials in the food industry because they possess
strong antibacterial activities. This plant is known to be nontoxic as it has
been consumed by a human for centuries without showing any toxic character.
Further studies will be done in the pipeline to check out the bio-active
compound that many organic extracts of L.japonica have. In addition, further
research is needed in order to gain information based on the practical
efficiency of essential oil or extracts to inhibit the growth of food-borne and
spoilage microbes under specific application conditions (Rahman & Sun, 2009)

Another research has been
done on 2012, to determine the antimicrobial potential of six essential oils
(EOs) that are Origanum vulgare, Cinnamomum cassia, Brassica hirta, Thymus
vulgaris, Satureja montagna, and Cymbopogon nardus, with four bacteriocins
which are nisin, pediocin, and two bacteriocins produced from our isolated
Enterococcus faecium MT 104 and MT 162, with five pathogenic bacteria and two
spoilage bacteria. A synergistic or additive effect happen on several pathogens
due to combination use of EO with nisin or pediocin or bacteriocins produced by
strains MT 104 and MT 162 of E. faecium. This allows the lower concentration
usage of EOs; hence, manage to obtain two objectives at the same time. The
objectives achieved are the decrease in undesirable organoleptic impact and
controlling the growth of foodborne pathogen and spoilage bacteria in the food
(Turgis, Khanh, Dupont & Lacroix, 2012).

However, quality indices can
be formed from spoilage metabolites. Chemical analyses are significantly faster
compared with microbiological methods. The classical single-compound quality
index (SCQI) for marine food encompass calculations of entire volatile nitrogen
(TVN), TMA and hypoxanthine. Another method that can be used as quality indices
is by measuring the ratios between ATP degradation products (K values) and
biogenic amines. Combinations of several metabolites are

Multiple-compound quality
indices (MCQI), in which combinations of several metabolites are identified by
statistical methods, have recently been introduced and correlate better with
sensory properties and/or shelf life in some products. This new combination of
sophisticated chemical analyses, sensory assessment and multivariate statistics
will be an important area in food spoilage research in the years to come (Gram
& Dalgard, 2002).

6.    Conclusion

This literature review
emphasizes the importance of bacteria in the food industry. The bacteria,
yeasts, molds and viruses play significant roles in food processing in the food
industry as it helps in the fermentation process for producing many different
types of food such as cheese, dairy product and alcohol. The cheese also
produces cheese whey as a by-product which can be further fermented to produce
bio-ethanol and ruminant feeds supplement. Next, the bacteria also involve as a
probiotic which mainly are derives from the LAB which provides benefit in human
health above the nutrient required. These probiotics such as yoghurt drink,
benefit the consumer in higher growth and feed efficiency, prevent intestinal
disorders and pre-digestion of anti-nutritional factors present in the
ingredients. The LAB also can be used in bio-preservation as bactericidin is
produced which functioning to kill and inhibit the growth of spoilage caused by
the bacteria. The Enterobacter are classified as the most bacteria that cause
the foodborne disease. The crude and processed food consist many different
types of microbes which include foodborne disease bacteria although the
internal tissue of healthy plants considered sterile. The animal and birds
consumed by human also contaminated by the indigenous bacteria. Pathogens such
as Salmonella serovars, pathogenic Escherichia coli, Campylobacter jejuni,
Yersinia enterocolitica and Listeria monocytogenes can present in the animal as
carriers without showing symptoms. However, the crude honey can be used to
inhibit the growth of the foodborne disease bacteria. A current research has
been done where the growth of foodborne disease bacteria and microbes that
cause spoilage can be inhibited by using essential oil or organic extract of L.
japonica. Another current research states that the foodborne disease bacteria
can be inhibited efficiently by using six essential oil (EOs) that are Origanum
vulgare, Cinnamomum cassia, Brassica hirta, Thymus vulgaris, Satureja montagna,
and Cymbopogon nardus. On the other hand, the spoilage metabolites can be used
as quality indices, as chemical analyses are significantly faster compared with
microbiological methods.Use of MCQI where the combination of sophisticated
chemical analyses, sensory assessment and multivariate statistics also have
formed which suspected will be an important area in food spoilage research in
the years to come.

Post Author: admin

x

Hi!
I'm Jeremy!

Would you like to get a custom essay? How about receiving a customized one?

Check it out