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Microbes used in food industry
Nature uses microorganisms to carry out fermentation processes, and for thousands of years
Fermentation in food processing is the conversion of carbohydrates to alcohols and carbon dioxide or organic acids using yeast bacteria or a combination under aerobic or using yeast, bacteria, or a combination under aerobic or anaerobic conditions
Carbohydrates(sugar)
Alcohols + Organic acids + CO2
microbes
aerobic/anaerobic
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Microflora in fermented foods
Bacteriao Lactic acid bacteria : Leuconostoc mesenteroides, Lactobacillus
brevis, Pediococcus and Streptococcus sp.o Other bacteria : Bacillus, Acetobacter
Mould o Aspergillus, Rhizopus, Mucor, Actinomucor, Amylomyces, Neurospora
and Monascus
Yeast o Saccharomyces
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Benefits of fermentation
Preservation of food: some microbes could be produced antimicrobial substances (organic acid, ethanol, bacteriocin) against spoilage and pathogenic microorganisms
Fermentation to peel seed coat (eg. cocoa, coffee, pepper) with natural microorganisms (lactic acid bacteria, acetic acid bacteria and yeast)
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Benefits of fermentation
Biological enrichment:
o Probiotic bacteria/lactic bacteria
o Essential amino acids, vitamins, essential fatty acidsy
Enrichment of the diet through development of a diversity of flavors, aromas, and textures in food substrates into new product
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Fermentation
http://academic.pgcc.edu/~kroberts/Lecture/Chapter%205/fermentation.html6
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Type of fermentation
Alcohol fermentation
Acetic acid fermentation
Lactic acid fermentationLactic acid fermentation
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Alcohol fermentation
8 http://www.uic.edu/classes/bios/bios100/lectures/respiration.htm
Alcohol fermentation
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Acetic fermentation
Alcohol + O2 + Acetobacter spp. acetic acid + H2Oacetification
orGluconobacter
10 http://www.uic.edu/classes/bios/bios100/lectures/respiration.htm
Lactic acid fermentation
11ที่มา : http://porpax.bio.miami.edu/~cmallery/150/makeatp/c8.9x18b.lactic.acid.jpg
Lactic acid fermentation
Homofermenterso 85-90% of sugar were converted into lactic acid eg. Streptococcus faecalis,
Pediococcus cerevisiae
Heterofermenterso 50% of sugar were converted into lactic acid, 25% were converted into
d d h l d 2 % d COacetic acid and ethanol, and 25% were converted into CO2
o Leuconostoc mesenteroides, Leu. fermenti, Lactobacilli
o Foods : Yoghurt, fermented milk, cheese, fermented meat and vegetable
Facultative heterofermenterso Some species of Lactobacillus could display both of homo- and
heterofermenters
o Lb. plantalum, Lb. casei and Lb. sake
o Food: wine12
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Ferment-inhibiting substances Production of organic acids and decreasing of pH
Bacteriocins against other relative bacteria
o nisin (Lactococcus lactis)
Hydrogen peroxide (H2O2) Hydrogen peroxide (H2O2)o Aerobic fermentation: LAB produce H2O2 as electron acceptoro Anaerobic fermentation: small content of H2O2 were produced
by LABo Raw milk: H2O2 act as co-factor in Lactoperoxidase system
(lactoperoxidase+ H2O2 + thiocyanate)
Ethanol in the heterofermenter at anaerobic condition
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Pickled fruits and vegetables
LAB change sugar in fruit and vegetable to lactic acid
Microbes involved in the fermentation process: Lactobacteriaceae (Streptococcus, Pediococcus, Diplococcus, Leuconostoc and Lactobacillus)
Fermentation :o First stage of fermentation: LAB produce organic
acidso Last stage of fermentation: aciduric yeasts
and moulds
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Pickled fruits and vegetables
Change in appearance, texture, flavor, taste
Factors affecting the quality of pickled fruits and vegetableo pHo Oxygeno Fermenting temperatureo Salt concentrationo Starter microorganisms
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Kimchi
Kimchi is a traditional fermented Korean side dish made of vegetables with a variety of seasoning
Use different vegetable eg. cabbage, radish, cucumber, scallion
• Microbes involved in the fermentation process:
o Leuconostoc sp. : Leu. mesenteroides, Leu. kimchi
o Lactobacillus : Lb. plantarum, Lb. brevis
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Change in LAB in fermented kimchi
Leu. mesenteroides + vegetable + brine + ingredients(Facultative anaerobic condition)
lactic acid + acetic acid + CO2 + ethanol (pH = 4.6-4.9)
Growth of Lb. plantarum, Pediococcus cerevisiae,
Lb. brevis, Lb. fermentum
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Sauerkraut
Sauerkraut = sour cabbage
Finely cut cabbage fermented by various LAB: Leuconostoc, Lactobacillus, Pediococcus
Salt plays an important role in initiating the sauerkraut p y p gprocess and affects the quality of the final producto withdraw juice from the cabbage o Adjust anaerobic conditiono Inhibit undesired microorganismso making a more favourable environment for development of the
desired bacteriao contribute to the firmness
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Microbes involved in the fermentation process of Sauerkraut
Anaerobic LAB o Production of lactic acid, acetic acid, formic acid,
succinic acid causing pH to decrease and inhibited spoilage aerobic bacteriaspoilage aerobic bacteria
Facultative anaerobic LAB Leu. Mesenteroides grow rapidly at low pH value,
produce large contents of lactic and acetic acids
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Microbes involved in the fermentation process of Sauerkraut
Homofermentative lactobacilliGrowing of Lactobacilli (Lb. plantarum, Lb. sakei, Lb.
curvatus) and cocci (streptococci and pediococci) Converting of sugar (glucose, fructose, sucrose) into Converting of sugar (glucose, fructose, sucrose) into
lactic acid
Heterofermentative lactobacilli the last stage of sauerkraut fermentation ferment pentose sugar (arabinose, xylose)
into lactic acid
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Wine
Wine is an alcoholic beverage made from fermented
grapes or other fruits
Production process:
Grape (crushing) + S. cerevisiae alcohol fermentationp ( g) f
Packaging aging/maturation malolactic fermentation(clarification)
(sugar) Bacterial fermentation
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Wine
Source of fermenting microbials:o Starter: usually use S. cerevisiaeo Grape : yeast, mould, LAB, AABo Equipment
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Malolactic fermentation
L-malic acid L-lactic acidLeuconostoc oenos fermentation
Decaboxylationecabo y at o
CO2
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Vinegar
Vinegar is a liquid consisting mainly of acetic acid and water
The acetic acid is produced by the
fermentation of ethanol b acetic acid fermentation of ethanol by acetic acid
bacteria
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Vinegar: 2 step of fermentation
acetic acid bacteria (Aectobacterspp., Gluconobacter, A. pasteurianus)
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Acetification
Alcohol + Acetobacter spp. aldehydes
Alcohol dehydrogenase
Acetic acid
Aldehydedehydrogenase
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Miso (Japanese)
Also called Chiang (Chinese), Jang (Korean)
Various types
rice miso barley miso soybean miso
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Miso fermentation
Polished rice
Soaked
Cooked
IncubatedK
oji m
akin
g p
roce
ss
Seed mold
Whole soybean
Soaked
Cooked
Salt
Aspergillus oryzae
Koji
KB
rine
ferm
enta
tion
pro
cess
YeastLactic acid bacteria
Mixed
Fermented
Aged
Mashed
Miso
Saccharomyces rouxii, Zygosaccharomyces spp.
Lb. acidophilus, Lb. delbrueckii, Pediococcus
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Koji
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Tempeh Tempeh is a fungal fermented soybean
food originating from Indonesia The fungal enzyme activity causes
significant decomposition of polymeric components, as well as a
id bl difi ti f b considerable modification of soybean flavonoids.
Usually used Rhizopus oligosporus, other such as R. oryzae, R. stolonifer
Tempeh offers a number of proven health benefits including excellent digestibility and protection against diarrhea and chronic degenerative diseases.
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Tempeh
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Tempeh
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Potential Strains Selected for Improvement of Active Substances in Tempeh fermentation
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Sufu
Su-fu (Chinese cheese) or tao-hu-yi in Thailand
Sufu originated in China but is also prepared in other Asian countries where variations of sufu exist.
Sufu is consumed as an appetizer and a side dish, e.g. with breakfast rice or steamed-bread.
Sufu is a highly flavoured, creamy cheese-like product, so it would be expected to be suitable for use in western countries as a healthy, non-cholesterol food from plant origin.36
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Sufu Most sufu products are produced by a similar principle, which involves four main steps:(1) Preparation of tofu(2) Preparation of pehtze(3) Salting ( ) g(4) Ripening
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Sufu
According to the colour and flavour, sufu can be classified into four types
Red sufu -mainly consists of salt, angkak (Monascus-fermented rice), alcoholic beverage, sugar, flour (or soybean) paste and some spices.
White sufu - similar ingredients as red sufu in the dressing mixture but without angkak
Grey sufu - contains the soy whey left over from making tofu, salt and some spices.
Other types - made by adding various ingredients to the dressing, including vegetables, rice, bacon, and even higher concentrations of alcohol
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Sufu
According to fermenting microbes, sufu can be classified into four types:
1) Mould-fermented sufu – used Mucor racemosus, M. hiemalis and Actimomucor elegans in the pizi production
2) Naturally fermented sufu - used natural microbes in the piziproduction
3) Bacteria-fermented sufu – inoculated bacteria eg. Bacillus sp. or Micrococcus sp. into maturation process
4) Enzymatically ripened sufu
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Thua Nao/Natto Thua Nao (Thai)/Natto (Japanese) are
Bacillus-fermented soybean
Bacillus subtilis and related bacilli (i.e., B. licheniformis and B. pumilus) are usually found to be dominant microflora of the found to be dominant microflora of the fermented soybeans
A major activity in the fermentation is the hydrolysis of proteins to peptides and amino acids which are responsible for the typical ‘umami’ taste in fermented soybeans
Thua Nao
Natto40
Traditional Natto Process
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Traditional Thua Nao Fermentation
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Thua Nao VS Natto Production
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Thua Nao
Thua Nao Kab Roasted Thua Nao Mer Steamed Thua Nao Mer
Nam Ngearw Curry Chilli paste
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Natto
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Natto Foods
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Thua Nao/Natto
The utilisation of soybean protein by bacteria leads to free amino acids formation
Typical characteristics of traditional fermented soybeans are distinct ammoniacal smell, brownish colour, palatable taste and seed covered
ith b t with mucous substance.
Isoflavones are phytoestrogens that are abundant in soy-fermented foods and have been related to several health benefits.
Pharmacological and antioxidant properties of soy isoflavones are involved in prevention of breast cancer, antihypertensive effect, reduced risk of cardiovascular diseases, improvement of bone health, reduced menopause symptoms, antimutagenic effects and antidiabeticeffects.47
Improvement of Thua Nao Production
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Starter culture/Thua Nao powder
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Fermented ground pork (Nham) Nham is an uncooked, fermented semi-dry Thai
sausage
It is made from fresh lean pork, pork skins, cooked rice, fresh garlic and eye bird chillies
The sausage is wrapped in banana leaves or g ppsynthetic casings and fermented for 3-5 days
Rice act as a source of carbohydrates for lactic acid production during fermentation
LAB fermentation :o early stage of fermentation usually found Pediococcus
cerevisiae, hetrofermentative LAB
o last stage - Lb. plantarum and Lb. brevis fermentation
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Improved Nham Fermentation
Pure starter culture for fermenting Nham : o Lb. plantarum
o Lb. curvatus
o Pediococcus pentosaceuso Pediococcus pentosaceus
o Ped. acidilactici
Mixed 3 microbes:o Lb. plantarum
o Pediococcus serevisiae
o Micrococcus varians
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Salami Salami is cured sausage, fermented and
air-dried meat
Ingredients included pork or meat, minced fat, red wine, garlic, spices
LAB fermentation LAB fermentation
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Fish sauce
Fish sauce is a clear, amber to reddish brown liquid with a predominantly salty taste and characteristic aroma.
It is obtained from the hydrolysis of fish with salt through natural fermentation for 6–12 months
Fish sauce is well recognized as a food flavoring by the people in Southeast Asia for many centuries.
Hydrolysis of fish protein results in small-molecule peptides, nitrogen compounds, and amino acids.
Fish sauce contains about 20 g/L of total nitrogen, of which 80% is in the form of amino acids.
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Local Names of Fish Sauce in Different Countries
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Fermented milk
Dairy starter cultures are microorganisms that are intentionally added to milk in order to create a desired outcome
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in the final product, most often through their growth and “fermentation” processes.
Fermented milk
Fermented milk products such as yogurt, kefir, buttermilk, and acidophilus milk are gaining increasing attention.
F d lk
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Fermented milks containing probiotics could be used to prevent and/or cure some important diseases (such as intestinal- and immune-associated diseases).
Fermented milk
The most common use of starter cultures is for the production of lactic acid from lactose (milk sugar), which in most cases causes or assists in the coagulation of milk protein by lowering its pH value.
C l h d l d ll f d
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Cultures that produce lactic acid are generally referred to as “lactic acid bacteria” (LAB) such as Lactobacillus, Lactococcus and Leuconostoc.
Milk + LAB Lactic acid + Acetic acid + CO2 + (lactose) Flavor compounds (diacetyl,
acetaldehyde)
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Fermented milk
The fermentation process increases the shelf-life of the product, while enhancing the taste and improving the digestibility of milk.
Starter organisms can also influence flavor and texture of cultured and/or aged products through the
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of cultured and/or aged products through the breakdown of proteins, fats and other milk constituents in addition to the pH effect.
The lower pH of cultured products can be inhibitory to certain spoilage organisms, although inhibition is also associated with other by-products of growth with some starters.
Fermented milk
Probiotic cultures are organisms that have some claimed health benefit for those that consume them, e.g., better digestion, anti-cancer compounds, and prevention of heart disease.
Probiotic cultures may be added as adjuncts or they may
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Probiotic cultures may be added as adjuncts or they may be directly involved in the fermentation process.
Lactic acid bacteria Lactic acid production: Streptococcus lactis, S. cremoris
and S. thermophilus
Flavour production : S. diacetilactis and Leuconostoccitrovorum
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Fermented milk usually use mixed starter culture
o Starter D: S. cremoris+ S. lactis +S. diacetilactis
o Starter DL: S. cremoris +S. lactis+ S. diacetilactis +Leuconostoccitrovorum
o Starter L: S. cremoris +S. lactis+ Lb. citrovorum
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Dairy Starter Cultures
Major Function Product UseMesophilic starters
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Dairy Starter Cultures
Major Function Product UseThermophilic starters
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Type of fermented milk
Mesophilic starter fermented milk
Butter milko Fermented pasteurized skim milk with mesophilic LAB
eg. Lactococcus and Leuconostoc at 19-22C for 15-20 h
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Sour creamo Fermented milk butter with Streptococcus and Leuconostoc at 20-
22C until pH decreased at 4.5
Fermented milko Langfilo Filmjolko Ymer
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Type of fermented milk
Mesophilic and thermophilic starter fermented milk
Yoghurto Fermented milk with Strep. thermophilus (mesophilic) and
Lb. bulgaricus (thermophilic) (ratio 1:1)
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Yakulto Fermented skim milk with Lb. casei at 37C for 4 days
Bulgarian butter milko High acid fermented butter milk, fermented by 2% Lb. bulgaricus
at 38 – 42 C for 10-12 h
Type of fermented milk
Mesophilic and thermophilic starter fermented milk
Acidophilus milk o Fermented sterilized milk with 2-5% Lb. acidophilus at 38C for
18-24 h
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Probiotic fermented milko Fermented milk with LAB (Lb. acidophilus, Lb. casei) and
probiotic (Bifidobacterium) acidophilus at 38C for 18-24 h
Type of fermented milk
Alcohol-lactic fermentation
Kefir o Fermented milk with LAB (Lactococci, Leuconostoc, Lactobacilli)
and yeast (Candida, Kluyveromyces, Saccharomyces) at 20-25C and 8 10C
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8-10C
Kumisso Russian fermented milk, fermented with Lb. bulgaricus and
Candida kefir at 18-20C and 4-6C
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Health benefit microorganisms
Usually according “probiotic ” (meaning “for life)
Probiotics are live microorganisms, which when administered in adequate amounts, confer a health benefit on the host
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Prebiotic a selectively fermented ingredient that allows specific changes, both in the composition and/or activity in the gastrointestinal microflora that confers benefits upon host well-being and health
Prebiotic = oligofructose, fructooligosaccharides, inulin and polyfructose
Probiotics
Lactobacillus species Bifidobacterium species Other
L. acidophilus B. bifidum Bacillus cereus
L. casei B. longum Eschericia coli
L. reuteri B. breve Saccharomycescerevisiae
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L. bulgaricus B. infantis Saccharomycesboulardii
L. plantarum B. lactis Enterococcus faecalis
L. johnsonii B. adolescentis Strep. thermophilus
L. lactis Trichuris suis
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Mechanisms of Action of Probiotics
Produce antimicrobial substances (organic acids or bacteriocins)
Upregulate immune response to possible pathogens or to vaccines
Downregulate inflammatory response
Assist in early programming of the immune system to result in a
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y p g g ybetter balanced immune response and reducing risk ofdevelopment of allergy
Improve gut mucosal barrier function
Enhance stability or promote recovery of commensal microbiota
Deliver functional proteins (eg, lactase) or enzymes
Decrease pathogen adhesion
Health benefits
Prevention and treatment of diarrhea
Treatment of chronic inflammatory bowel disease
Treatment of ischemic bowel disease and bacterial infections in children born prematurely
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The immune system of the body
Treatment of allergies
Prevention of colon cancer
Treatment of fungal vaginitis
Reduces blood cholesterol levels