Fermented milk 1

fermented milk products.

1. Y MANUFACTURING OF DIFFERENT FERMENTED MILKS AND THEIR MICROBIOLOGICAL AND CHEMICAL ANALYSIS . BY:SHAILJA KUMARI MTECH 2 nd YEAR DAIRY MICROBIOLOGY

2. HISTORY Louis Pasteur (1822–1895), during the 1850s and 1860s, showed that fermentation is initiated by living organisms . In 1857, Pasteur showed that lactic acid fermentation is caused by living organisms. In 1860, he demonstrated that bacteria cause souring in milk, his work in identifying the role of microorganisms in food spoilage led to the process of pasteurization.

3. FERMENTATION Fermentation is a metabolic process in which an organism converts a carbohydrate such as starch and sugar into alcohol and/or acid. Lactic acid fermentation  is a metabolic process by which glucose and other six carbon sugars (also, disaccharides of six-carbon sugars, e.g. sucrose or lactose) are converted into cellular energy and the metabolite lactate.

4. TREE OF FERMENTED MILKS

5. FERMENTED MILKS Fermented milk products , also known as  cultured dairy foods ,  cultured dairy products , or  cultured milk products , are dairy foods that have been fermented with Lactic acid bacteria such as Lactobacillus, Lactococcus and Leuconostoc .  The fermentation process increases the shelf-life of the product, while enhancing the taste and improving the digestibility of milk. About 2.3% of the total dairy product market is in the form of cultured dairy product.  It has great therapeutic benefits and nutritional value.

6. COMPOSITION The typical composition of fermented milk as per Codex standard (243-2003) is given below : The pH range is 3.8 – 4.6 CONSTITUENTS LEVEL (%) Dry matter 14-18 Protein Min 2.7 Fat Less than 15 Lactose 2-3 Lactic acid Min 0.3 Carbohydrates 5-25

7. FERMENTED MILK PRODUCTS YOGHURT DAHI KEFIR KUMISS BULGARIAN SOUR MILK ACIDOPHILUS MILK CULTURED BUTTERMILK CULTURED SOUR CREAM LEBEN TAETTE (SCANDINAVIAN ROPY MILK) SKYR CHEESE

8. YOGURT Food produced by bacterial fermentation of milk. Yogurt is produced using a culture of  Lactobacilius delbruecki subsp.bulgaricus and Streptococcus thermophilus bacteria. In mixed cultures, the final concentrations of acetaldehyde in yogurt can range from 2.4µgg⁻¹ to 41.0 µgg⁻¹ and these levels, along with lower amounts of acetone (1.0-4.0µgg⁻¹), acetoin (2.5-4.0µgg⁻¹), and diacetyl (0.4-13.0µgg⁻¹ ), give yogurt its distinctive flavor profile. Titratable acidity 0.7% coliform count <10/g yeast& mold count <100/g.

9. TYPES OF YOGURT Greek yogurt Stirred yogurt Drinking yogurt Set yogurt Frozen yogurt Flavoured yogurt

10. MANUFACTURE OF YOGURT

11. DAHI Dahi is a product made by fermenting milk of the cow or water buffalo milk with lactic acid bacteria. Dahi typically contains a mixture of S. thermophilus , Lc . lactis subsp. lactis , Lc . lactis subsp. cremoris , Lc . lactis subsp. Lactis ( biovar . diacetylactis ), Lb. helveticus , Lb. casei , and Lb. acidophilus. The pH is 4.5–4.7. Titratable acidity 0.7% Coliform count <10/g , Yeast & mold count <100/g . Constituents Level (%) Water 85-88 Fat 5-8 Protein 3.2-3.4 Lactose 4.6-5.2 Ash 0.7-0.75 Lactic acid 0.5-1.0 Calcium 0.12-0.14 Phosphorous 0.09-0.11

12. MANUFACTURE OF DAHI Receiving milk Preheating (35-40˚C) Filtration/clarification Standardization (SNF 9-11%) Preheating (60 ˚C) Homogenization (176kg/sq.cm) Pasteurization(80-90 ˚C/15-30min) Cooling(22-25˚C) Inoculation(1-3% lactic starter) Packaging Incubation(22-25 ̊ C/16-18h) Dahi Cooling & storage (5̊ C)

13. KEFIR Fermented milk drink that originated in the north Caucasus Mountains made with kefir "grains", a yeast/bacterial fermentation starter. Organism- str. Lactis , beta bacterium causasicum , yeast Lactic acid – 0.9-1% Alcohol – 0.5-1% Carbondioxide - 0.03-0.07% There are traces of acetaldehyde, diacetyl and acetoin . of the total nitrogen,7% is in the form of peptones and 2%amino acids. Increase in vit B1, B2& Folic acid.

14. Your Text Here MANUFACTURE OF KEFIR

15. KUMISS Kumiss is a type of fermented dairy product made from mare’s milk. Produced from a liquid starter culture.  Kumiss has a higher alcohol content than kefir. Organism – Lactobacillus/Bacterium orienburgii , Lactobacillus bulgaricus , . L. acidophilus , yeast a) Lactic acid –0.7-1.8% b) Alcohol – 1-2% c) Carbondioxide - 0.5-0.9% d) Ethanol – 1.3% e) Lactose – 2.3% f) Fat – 1.5% g) Protein – 2.0%

16. MANUFACTURE OF KUMISS

17. BULGARIAN SOUR MILK Bulgarian sour milk comes under the general category of yogurts which contain live bacteria. It is a wonderful probiotic food. It is prepared – using a combination of the two strains: Lactobacillus Bulgaricus and Streptococcus Thermophilus .

18. MANUFACTURE OF BULGARIAN SOUR MILK Sour milk (goat or cow’s milk) Inoculation ( L.bulgaricus & S. thermophilus culture) Ripening (40-45 ̊C) Incubation (37 ̊C) Acidity (1.4%) Storage & packaging (7 ̊C)

19. ACIDOPHILUS MILK Milk fermented by live cultures of the bacterium acidophilus and consumed especially to promote intestinal health. This cultured product is usually low in fat and has a longer shelf life than ordinary milk. Acidophilus milk is usually not recommended for people who have immune system problems.  Lactobacillus acidophilus used as a starter culture. Lactic acid – 1.0% (0.6-0.7 for medicinal use) Lactobacillus counts 2000-3000million/ml

20. MANUFACTURE OF ACIDOPHILUS MILK Receiving milk (skim/whole/defatted) Filtration/Clarification (35-40 ̊C) Homogenization Sterilization (115 ̊C/15 min) Cooling (38 – 40 ̊C) Inoculation (3-5 %) Incubation (38-40 ̊C/12-16h) Coagulation Break-up of coagulum Cooling (10 ̊C) Packaging & storage (5 ̊C)

21. CULTURED BUTTERMILK Fermented dairy product known as cultured buttermilk is produced from cow's milk and has a characteristically sour taste caused by lactic acid bacteria. This variant is made using different strains of bacteria—either  Lactococcus lactis  or  Lactobacillus bulgaricus , S. lactis subsp . diacetylactis Leuco.citrovorum which creates more tartness , flavour and aroma. Acidity 0.8-0.85% LA Fat 0.5-3%

22. MANUFACTURE OF CULTURED BUTTERMILK Receiving skim milk Filtration Pasteurization (82 – 88 ̊C/30 min) Cooling (22 ̊C) Inoculation (1-2%) Incubation (21-22 ̊C) Coagulation (12-16 h) (0.80-0.90% LA) Creaming Break-up of coagulum Adding butter granules Cooling (5-10 ̊C) Packing & Storage (5-10 ̊C)

23. CULTURED SOUR CREAM It is a extremely viscous product with the flavour and aroma of butter milk but with the fat content of 12-30% The starter culture Lactococcus and Leuconostoc species are used. The pH should be 6.2-6.3 Sour cream typically has a clean acidic flavor with hints of diacetyl . It is consumed as a dressing of topping on other foods such as fruits .

24. MANUFACTURE OF CULTURED SOUR CREAM Fortification of whole milk with cream(20% fat) Heating(80˚C/30 min) Homogenization (2000 psi) at 60-80˚C Cooling (21˚C) Inoculation (0.5-1.0 % butter starter) Incubation(21˚C until acidity reaches 0.6%) Cooling (5˚C) Packaging

25. SKYR It is a traditional Icelandic milk product which contain 7.6% SNF, 8% sugar, 0.3% pectin, is homogenize and pasteurized at temperature 73˚C for 20 sec. Skim milk is fermented with S. thermophilus , L. bulgaricus , L. helveticus lactic acid bacteria similar to those used for yogurt along with lactose-fermenting yeasts. Addition of rennet. pH should be maintained 4. Chemical composition of Skyr Constituent Level in Skyr Skyr whey Dry matter % 16.72 5.66 Protein % 11.54 0.48 Fat % 0.19 - Lactose % 4.41 4.40 Lactic acid % 1.75 0.94 Ash % 0.78 0.75

26. MANUFACTURE OF SKYR Pasteurised skim milk Rennet 0.01-0.1% fresh skyr (S. thermophilus + L. bulgaricus + L. helveticus ) Fermentation(40˚C) Acid curd(4.65) Fermentation at 17 ˚C for 16-18h(pH4.4) Skyr curd in whey Heating to 67˚C/15sec Cooling(30˚C) Separation in a quarg separator Whey (5% dry material) Skyr (16-17% dry material) Ultrafiltration (50˚C) Retentate (16-17% dry material) Permeate Whey drink with fruit juice

27. LEBEN Leben  is used across the Arab World (Middle East and North Africa),to refer to a food or beverage of fermented milk. Generally, there are two main products known as  leben : in the Levant region, yogurt; and in Arabia and North Africa (Maghreb), buttermilk. There is a mixed microflora consisting of S. lactis , S. thermophilus , L. bulgaricus and lactose fermenting yeasts. Labneh has 7–10% fat

28. MANUFACTURE OF LEBEN Milk (in earthenware containers) Inoculation with sample from previous batch Incubation at ambient temperature until firm coagulum production Churning with gradual addition of warm water Heating Butter Butter oil Addition of Fenugreek seeds Leben Cooling Packing

29. TAETTE Taette is a moderately ropy and sour milk product of slightly flowing consistency which contains not more than 0.3-0.5% of alcohol. This product is used in Scandinavian countries in Finland.It is produced mainly by fermenting fresh milk with a strain of S.lactis var.hollandicus and yeasts such as Saccharomyces taette . Composition : a) Lactic acid – 1.0% b) Alcohol – 0.3-0.5% c) Acetic acid – Traces d) CO 2 - Saturation level

30. MANUFACTURE OF TAETTE Fresh cow’s milk Inoculation with leaves of butterwort (1%) Addition of starter ( Saccharomyces major taette,L.taette,Bacillus acidactislogus ) Maturation (2-3 days at less than 10 ̊C) in wooden cellars ‘ Taette ’

31. CHEESE Cheese  is a food derived from milk that is produced in a wide range of flavors, textures, and forms by coagulation of the milk protein casein. During production, the milk is usually acidified, and adding the enzyme rennet causes coagulation. Traditional  pasta filata  cheeses such as Mozzarella also fall into the fresh cheese category. Fresh curds are stretched and kneaded in hot water to form a ball of Mozzarella. Cheddar cheese  is a relatively hard, off-white (or orange if spices such as annatto are added), sometimes sharp-tasting (i.e., bitter), natural cheese. Originating in the English village of Cheddar in Somerset.

32. DIFFERENT TYPES OF CHEESE Roquefort Feta Gouda Mozzarella Swiss Ricotta Cheddar Brick Parmesan

33. MANUFACTURE OF CHEESE

34. COMPOSITION OF DIFFERENT TYPES OF CHEESE Types of cheese Moisture % Fat % Protein % Calcium % Vitamins Vit A Thiamin Riboflavin (µg/100g) (µg/100g) (mg/100g) Energy content (Kcal/100g) Hard (Cheddar) 35.0 33.0 26.0 0.83 380 50 0.50 400 Semi-hard (Edam) 43.0 24.0 26.0 0.76 250 60 0.35 320 Blue-veined (Roquefort) 40.0 31.0 21.0 0.32 300 30 0.70 360 Soft (Camembert) 51.0 23.0 19.0 0.39 240 50 0.45 280 Unripened (Cottage) 79.0 0.4 16.9 0.09 3 30 0,28 82

35. MICROFLORA OF DIFFERENT CHEESE CHEESE STARTER COMPOSITION Cheddar S. lactis , S. cremoris , S. diacetylactis Gouda S. lactis , S. cremoris , S. diacetylactis , Leuconostoc spp. Cottage S. lactis , S. cremoris , Leuconostoc spp. Swiss S. thermophilus , L. helveticus , Propionibacterium shermanii Brick S. lactis , S. cremoris , S.thermophilus , Brevibacterium linens Mozzarella S.thermophilus or S. faecalis & L. bulgaricus Blue (Roquefort) S. lactis , Penicillium roqueforti Camembert S. lactis , Penicillium camemberti

36. MICROBIAL ANALYSIS FOR DIFFERENT FERMENTED MILK PRODUCTS pH/Count Stirred yogurt Set yogurt Cultured milk Cultured butter milk Cultured cream Kefir pH after cooling 4.0-4.2 4.2-4.4 4.3-4.5 4.4-4.6 4.4-4.7 4.4-4.3 Coliforms (per g) < 1 < 2 < 0.1-1 < 1-10 < 10 < 0.3-10 Yeasts & molds (per g) < 1-10 < 1-10 < 1-10 < 10 < 10 - Others (per g) < 100-1000 < 100 < 100 < 10-100 < 10-100 - Salmonellae (per 25g) < 1 < 1 - - - - Staphylococci (per g) < 1 - - - - - Enterococci - ? - - - - Clostridia (pre g) < 1 - - - - - B. Cereus (per g) - - < 100 - - < 100

37. CHEMICAL ANALYSIS FOR DIFFERENT FERMENTED MILK PRODUCTS Dahi Yogurt Kefir Kumiss Acidophilus milk Butter milk Cultured cream Cheese pH 4.8 4.3 5.1-4.7 4.5-4.7 4.6 6.6-8.0 4.5-4.8 5.1-5.9 Fat% 5-8 1.7 0-4 1.5 0.5-2 0.5-3 12-30 33 Moisture % 86 87 86.3 13.5 - - - 35 Protein% 3.2-3.4 3.5 4.5 2.0 3.9 3.3 3.1 26 Acidity% 0.5-1.1 0.7 0.9-1.1 0.7-0.9 1 0.85 0.85-1.0 - Alcohol% - - 0.1-1.0 1-2 - - - -

38. Some other microbial and chemical analysis Alfatoxin (M1) maximum level is 50ng/ kg.In some cattle feed alfatoxin (B1) is also present. Pesticide level: The products are contaminated with organochlorine & organophosphorus pesticide residue with 0.094mg/kg. Antibiotic residue: for detection two test are performed eclipse and biosensor test. Antimicrobial activity:LAB generally produce bacteriocin that has potential of biopreservative and have bactericidal action.

39. CONCLUSION Chemical and microbial analysis we got to know about bacterial count susceptible to health. Different microflora provide different health promoting metabolites. Proper manufacturing is one of important process to increase the shelf life of different products. Therapeutic values such as lowering blood pressure strengthening the vital organs and provide immunity. Ability to compete with normal microflora and resistance to bacteriocin , acids and others antimicrobial agents and other inhibitory agents.. Fermented milk products have multiple health benefits.