Role of microoganisms in fermentation

presented by HAFIZ M WASEEM
university of education LAHORE Pakistan
i am from mailsi vehari and studied in lahore
bsc in science college multan
msc from lahore

1. ROLE OF MICROORGANISMS IN FERMENTATION HAFIZ M WASEEM UNIVERSITY OF EDUCATION LAHORE

2. CONTENTS Introduction How fermentation works Advantages Types Fermenters and its types Main types of microorganisms in global food fermentation Controling factor in industrial fermentation Probiotics and its effects Types of fermented food Examples Conclusion

3. What is fermentation Fermentation is any metabolic process in which microorganisms’ activity creates a desirable change in food and beverages, whether it’s increasing flavor, preserving foodstuffs, providing health benefits, or more. The word “ferment” comes from the Latin verb “fervere,” which means “to boil.” Ironically, fermentation is possible without heat.

4. History The earliest record of fermentation dates back as far as 6000 B.C. in the Fertile Crescent—and nearly every civilization since has included at least one fermented food in its culinary heritage Louis PasteurOur modern understanding of the fermentation process comes from the work of the French chemist Louis Pasteur (Figure 2). Pasteur was the first to demonstrate experimentally that fermented beverages result from the action of living yeast transforming glucose into ethanol.

5. How fermentation work? Microorganisms survive using carbohydrates (sugars, such as glucose) for energy and fuel. Organic chemicals like adenosine triphosphate (ATP) deliver that energy to every part of a cell when needed. Microbes generate ATP using respiration. Aerobic respiration, which requires oxygen, is the most efficient way to do that. Aerobic respiration begins with glycolysis, where glucose is converted into pyruvic acid. When there’s enough oxygen present, aerobic respiration occurs.

6. Contin. Fermentation is similar to anaerobic respiration—the kind that takes place when there isn’t enough oxygen present. However, fermentation leads to the production of different organic molecules like lactic acid, which also leads to ATP, unlike respiration, which uses pyruvic acid. Depending upon environmental conditions, individual cells and microbes have the ability to switch between the two different modes of energy production. Organisms commonly obtain energy anaerobically through fermentation, but some systems use sulfate as the final electron acceptor in the electron transport chain.

7. What happens during fermentation? Beneficial microbes break down sugars and starches into alcohols and acids, making food more nutritious and preserv it . Fermentation products provide enzymes necessary for digestion. This is important because humans are born with a finite number of enzymes, and they decrease with age. Fermented foods contain the enzymes required to break them down. Fermentation also aids in pre-digestion.

8. What are advantages of fermentation? Probiotics aid the immune system because the gut produces antibiotic, anti-tumor, anti-viral, and antifungal substances, and pathogens don’t do well in the acidic environmet fermented foods create. Fermentation also helps neutralize anti-nutrients like phytic acid, which occurs in grains, nuts, seeds, and legumes and can cause mineral deficienciess Fermentation can increase the minerals in food and make them more available for absorption.

9. Types of fermentation Ethanol fermentation Yeasts break pyruvate molecules the output of the metabolism of glucose (C6H12O6) known as glycolysis in starches or sugars down into alcohol and carbon dioxide molecules. Alcoholic fermentation produces wine and beer.

10. Acetic acid fermentation Acetic acid fermentation. Starches and sugars from grains and fruit ferment into sour tasting vinegar and condiments. Examples include apple cider vinegar, wine vinegar, and kombucha.

11. Lactic Acid Fermentation LAB(Lactic Acid Bacteria) has very big importance industries and is used for milk preservation, fermentation and cheese, yogurt, and butter milk. Species from the Gram Positive bacteria group are used which includes the genera Lactobacillus, Le, Lactococcus, Streptococ cus and  Pediococcus .

12. Role of lactic acid in fermentation LAB plays vital role in fermentation of milk and milk products. Various LAB strains are used as starter cultures in milk industry. These starter cultures were collected from sequence activity of LAB and then they were isolated, selected and confirmed. LAB has most important property to acidify milk and gives texture and flavor because of converting milk protein. Fermented milk has characteristics to produce fresh acid taste like yogurt and cheese.

13. FERMENTERS Fermenter is an enclosed and sterlized vessel that maintains optimal conditions for the growth of microorganisms . It is a device in which a substrate of low value is utilized by living cells or enzymes to generate a product of high value. Extensively used for food processing , fermentation,waste material etc.

14. TYPES OF FERMENTERS Fermenters are of 4 types: Stirred tank reactor Airlift fermenters Tower fermenters Bubble up fermenters

15. Stirred tank reactor Smaller vessel is made up of glass while, lager vessels are made up of stainless steel of 1-1,000 or even 8,000L. They are closed system in which volumes are fixed. They are agitated with motor driven stirrer’s. It is a kind reactor with continuous flow culture system which is either of chemostat or turbidostat type.

16. Airlift fermenters It comprises of a gas light baffled riser tube or drought tube which is connected to the downcomer tube.

17. It is of two types: Internal- loop airlift bioreactor External loop airlift bioreactor These type of fermenters are commonly employed for aerobic bioprocessing technology. Because of their high efficiency, it is mostly preferred for production of methanol AIRLIFT FERMENTERS

18. Tower fermentation It was defined by Greenshields and co-workers. It is an elongated non-mechanically type of fermenters. There is unidirectional gases flow throughout the bioreactors. Tower fermenters are of following types: Bubble columns Vertical tower beer fermenters Multistage fermenters

19. Bubble up fermenters It is a bubble columns fermenters which have an internal cooling coil. Air is introduced from the bottom of the column.

20. Main types of microorganism in Global food fermentation Bacteria Fungi Yeasts Bacteria: Bacteria are the most dominant microorganisms in both naturally fermented foods or foods fermented by the use of starter cultures Types of bacteria: lactic acid bacteria Non lactic acid bacteria

21. Lactic acid bacteria Lactic acid bacteria are Gram-positive, catalase-negative bacteria that produce large amounts of lactic acid. The LAB comprise a large bacterial group consisting of about 380 species in 40 genera of 6 families, belonging phylogenetically to the order Lactobacillales within the phylum Firmicutes Common genera of the LAB isolated from various fermented foods of the world are Alkalibacterium , Carnobacterium , Enterococcus, Lactococcus , Lactobacillus, Leuconostoc , Oenococcus , Pediococcus , Streptococcus, Tetragenococcus , Vagococcus , and Weissella

22. Non-Lactic acid bacteria Species of Bacillus present in fermented foods mostly soybean-based foods are B. amyloliquefaciens , B. circulans , B. coagulans , B. firmus , B. licheniformis , B. megaterium , B. pumilus , B. subtilis, B. subtilis variety natto and B.thurin giensis Species of Bifidobacterium , Brachybacterium , Brevibacterium , and Propionibacterium have been isolated from cheese and other fermented milks.

23. Yeasts Genera of yeasts reported from fermented foods, alcoholic beverages and nonfood mixed amylolytic starters are Brettanomyces , Candida, Cryptococcus, Debaryomyces , Dekkera , Galactomyces , Geotrichum ,

24. Fungi Species of Actinomucor , Amylomyces , Aspergillus, Monascus , Mucor , Neurospora , Penicillium , Rhizopus , and Ustilago are reported from many fermented foods, Asian nonfood amylolytic starters and alcoholic beverages

25. Probiotics and its effect Probiotics are usually defined as microbial food supplements with beneficial effects on the consumers. Most probiotics fall into the group of organisms’ known as lactic acid‐producing bacteria and are normally consumed in the form of yogurt, fermented milks or other fermented foods.

26. Types of fermented food 1. Fermented milk foods 2. Fermented cereal foods 3. Fermented vegetable foods 4. Fermented soybean and non-soybean foods 5. Fermented meat products 6. Fermented fish products 7. Fermented root/tuber products 8. Fermented beverages and Asian amylolytic starters 9. Miscellaneous fermented products (fermented tea, cocoa, vinegar, nata , pidan , etc.)

27. FERMENTED MILKS : (i)lactic fermentations: consist of the thermophilic type (e.g., yogurt, Bulgarian buttermilk), probiotic type (acidophilus milk, bifidus milk), and the mesophilic type (e.g., natural fermented milk, cultured milk, cultured cream, cultured buttermilk) (ii)fungal-lactic fermentations: consist of alcoholic milks (e.g., koumiss, acidophilus-yeast milk), and moldy milks (e.g., viili)

28. Product Substrate Sensory Property and Nature Microorganisms Country Dahi Cow/buffalomilk, starter culture Curd, savory Lb. bifermentans, Lb. alimentarius, Lb. paracasei, Lact. lactis, Strep. cremoris, Strep. lactis, Strep. thermophilus, Lb.bulgaricus, Lb. acidophilus, Lb. helveticus, Lb. cremoris, Ped. pentosaceous, P. acidilactici, W. cibara, W. paramesenteroides, Lb. fermentum, Lb. delbrueckii subsp. indicus, Saccharomycopsis sp., Candida sp. Pakistan , India, Nepal, Sri Lanka, Bangladesh, Gheu/ghee Cow milk Soft, oily mass, solid, butter Lc. lactis subsp. lactis, Lc. lactis subsp. cremoris Pakistan, India, Nepal, Bhutan, Bangladesh,

29. FERMENTED CEREAL FOODS : Product Raw Material/ Substrate Sensory Property and Nature Microorganisms Country Jalebi Wheat flour Crispy sweet, donut-like, deepfried, snacks Sacch. Bayanus, Lb. fermentum, Lb. buchneri, Lact. lactis, Ent. faecalis, Sacch. cerevisiae Pakistan India, Nepal, Naan Wheat flour Leaved bread, baked Sacch. cerevisiae , LAB Pakistan, India, Afghanistan Rabadi Buffalo or cow milk and cereals, pulses Mild-acidic, thick slurry-like product Ped. acidilactici, Bacillus sp., Micrococcus sp.; Yeasts Pakistan, India

30. FERMENTED VEGETABLE PRODUCTS: Product Substrate/Raw Materials Sensory Property and Nature Microorganisms Country Cucumbers (pickles) Cucumbers Acidic, wet, pickle Leuc. mesenteroides, Ped. cerevisiae, Ped. acidilactici, Lb. plantarum, Lb. brevis Europe, USA, Canada Olives (fermented) Olive Acidic, wet, Salad, side dish Leuc. mesenteroides, Ped. pentosaceus; Lb. plantarum Lb. pentosus/Lb. plantarum, Lb. paracollinoides, Lb. vaccinostercus/ Lb. suebicus and Pediococcus sp. nonlactics (Gordonia sp./Pseudomonas sp., Halorubrum orientalis, Halosarcina pallid, Sphingomonas sp./ Sphingobium sp./Sphingopyxis sp., Thalassomonas agarivorans) and yeasts (Candida cf. apicola, Pichia sp., Pic. manshurica/Pic. galeiformis, Sacch. cerevisiae) USA, Spain,Portugal, Peru, Chile

31. FERMENTED LEGUMES: Soy sauce Soybean Alkaline, liquid Asp. oryzae, Asp. niger, Sacch. rouxii, Ped. acidilactis, Ped. cerevisae, Ped. halophilus, Lb. delbrueckii Worldwide Product Substrate/Raw Material Sensory Features and Nature Microorganisms Country

32. FERMENTED ROOT CROP AND TUBER PRODUCTS: Product Substrate/ Raw Materials Sensory Property and Nature Microorganisms Country Lafun/ Konkonte Cassava Submerged, staple Bacillus sp., Klebsiella sp., Candida sp., Aspergillus sp., Leuc. ,Corynebacterium manihot, Lb. plantarum, Micrococcus luteus, Geotrichum candidum West Africa

33. FERMENTED FRUIT PRODUCTS: Product Substrate/Raw Materials Sensory Property and Nature Microorganisms Country Achar/ chatney Fruits, vegetables, oil, salt Acidic, hot and sour, pickle LAB Pakistan, India, Nepal, Bangladesh

34. FERMENTED MEAT PRODUCTS: Product Substrate/Raw Materials Sensory Property and Nature Microorganisms Country Jerky Beef Dry, semi- dry, side dish LAB, yeast, molds, micrococci South America

35. FERMENTED, DRIED AND SMOKED FISH PRODUCTS: Product Substrate/Raw Materials Sensory Property and Nature Microorganisms Country Bagoong Alamang (Bagoong Isda, Bagoong) Fish/shrimp, salt Fish/shrimp paste, condiment Bacillus sp., Pediococcus sp. Philippines

36. VINEGAR : Product Substrate/Raw Materials Sensory Property and Nature Microorganisms Country Sirca Gur of molasses or grains Vinegar, seasoning Sacch. cerevisiae, Acetobacter sp. Pakistan Vinegar Sugar containing substrates Acetic acid flavored, liquid, condiment, seasoning Acetobacter aceti subsp. aceti, A. oryzae, A. pasteurianus, A. polyxygenes, A. xylinum, A. malorum, A. pomorum; Candida lactiscondensi, C. stellata,Hanseniaspora valbyensis, H. osmophila,Saccharomycodes ludwigii, Sacch. cerevisiae, Zygosaccharomyces bailii, Z. bisporus, Z. lentus, Z. mellis, Z. pseudorouxii, Z. rouxii Worldwide

37. COCOA/CHOCOLATES: Product Substrate/Raw Materials Sensory Property and Nature Microorganisms Country Coffee Coffee Flavored coffee, refreshing drink Ent. cloacae, Klebsiella oxytoca, Hafnia alvei, Lactobacillus, Leuconostoc, Weissella spp. Worldwide

38. EXAMPLES Fish sauce Soy sauce    Sauerkraut Pickles

39. CONCLUSION: Through fermentation technique, different types of food products can be obtained. Unfortunately, consumption of fermented food is repressed by modren life style and growing popularity of fast food. It is shamed! fermented food is not just tasty but extremely healthy, nutritious and important for well being of our body.