The document discusses various fermented dairy products. It provides information on the history and types of fermentation. Fermented dairy products are produced through the lactic acid fermentation of milk by bacteria such as streptococcus thermophilus and lactobacillus. Common fermented dairy products described include yogurt, kefir, cheese, and cultured buttermilk. The production processes and health benefits of specific products like yogurt and sour cream are also summarized.

1. Fermented dairy
products

2. Content
Introduction
History of fermentation
Why milk is fermented?
Types of fermented dairy products
Conclusion

3. • Fermentation is a metabolic process that produce chemical changes in organic substrates through
action of enzymes.
• 3 types of fermentation
i. Lactic acid fermentation
ii. Alcohol fermentation
iii. Acetic acid fermentation
• Milk products prepared by lactic acid fermentation or a combination of this & yeast fermentation are
called fermented dairy products.
• The microflora in milk is kept alive until sale to the consumers and may not contain any pathogenic
germs.
• The transformation of lactose in to lactic acid is the main fact.
• The most common strains used for fermentation of milk are streptococcus thermophilus usually in
association with Bifidobacteria or Lactobacilli.
Introduction

4. History of fermentation
 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 Pasteur was the first to demonstrate experimentally that
fermented beverages result from the action of living yeast transforming
glucose into ethanol.
 Slow techniques emerged among different cultures across the globe for
working with microbes.
 Early dairy farmers learned that by fermenting milk they could store
dairy products for much longer than they would in its raw state.

5. Why milk is fermented?
 Preservation: Bacteria are inhibited from growing through pH reduction when lactic
acid is formed, and shelf life is increased.
 Flavor Enhancement: The sour characteristics of fermented milk products comes from
fermentation products (lactic acid, carbon dioxide, ethanol) these products act as
excellent flavor carriers for herbs, spices, and other flavorings.
 Reducing Caloric content: Many fermented milk products come in low fat free varieties
and can be used substitute for higher fat ingredients.
 Texture Enhancement: Some fermented milk products (sour cream or crème fraiche) can
add body and thickness to sauces, dips or vinaigrettes.

6.  Emulsification: Milk proteins help stabilize fat emulsions in salad dressing, soups
and cakes.
 Foaming and whipping: Crème fraiche is capable of being whipped like whip
cream.
 Nutritional benefits: Fermented milk products may contain probiotics (bacteria that
are beneficial to health) as well as many vitamins and minerals. Fermented dairy
products contains with high nutritional components
Components of fermented
dairy products
Proteins
Carbohydrates
Minerals
Vitamins
Other by-products
Yeasts
Probiotics
Lipids
Prebiotics

7. Types of fermented dairy products
1. Mesophilic fermentation
• Cultured buttermilk
• Sour cream
2. Thermophilic Fermentation
• Yogurt
• Bulgarian Buttermilk
3. Yeast-Lactic Fermentation
• Kefir
• Kumiss

8. Fermented Dairy Products
Yogurt Curd Cheese Kefir
Cultured
butter milk
Sour cream Kumis Lassi
Acidophilus
milk
Leben

9. General steps in the preparation of fermented
dairy products
Raw milk
Standardization
The adjustment of one or more of
the milk constituents to meet the
legal requirement.
Homogenization
Mechanical treatment that mixes and
disperses that milk fat by using a high
pressure to break it down into smaller
particles.
Heat treatment
Main purpose is
to destroy
microorganisms
Inoculation
Incubation
Cooling Filling Cold storage

10. Yoghurt
• Yoghurt is semi-solid fermented milk product produced by the controlled fermentation of Cow’s milk by
two species of bacteria Lactobacillus bulgaricus and Lactococcus thermophilus.
• The lactose is fermented to lactic acid and it is the one which cause the characteristic curd to form.
• Streptococcus thermophilus brings the pH of the milk down to 5.5 and Lactobacillus bulgaricus converts
to lactose to lactic acid.
• Proteolytic enzymes from Lactobacillus bulgaricus break down milk proteins into peptides.
• These peptides stimulate the growth of Lactobacillus thermophilus which in turn produces formic acid
and carbon dioxide. These are the growth stimulants for Lactobacillus bulgaricus.
• The acidity gives yoghurt its tangy flavor, while the coagulated proteins result in a thickened, smooth &
creamy texture.
• Yoghurt (plain Yoghurt from whole milk) is Water 81% , Protein 9%, Fat 5%, Carbohydrate 4%,
including 4% sugars.

11. Types of yoghurt
1. Set yoghurt - Fermented in the pot in which it is sold, which gives it a firmer texture than other yoghurt
2. Stirred yoghurt – Is made from cultured milk that is incubated and cooled in a large vat, then stirred to
give
3. Drink yoghurt - Stirred yoghurt that has a low total solids content and which has undergone
homogenization to further reduce the viscosity
4. Flavored yoghurt - Add a spoonful of jam or fresh fruit to replicate popular commercial yoghurts. Add
sugar, honey, maple, syrup or any other sweetener to taste.
5. Concentrated/Greek yoghurt - Strained to remove most of its whey, resulting in a thicker consistency
than regular unstrained yoghurt, while still preserving the distinctive sour taste of yoghurt.
6. Frozen yoghurt - Frozen product containing the same basic ingredients as ice cream, but contains live
bacterial cultures.
Stirred yoghurt Frozen yoghurt
Drink yoghurt
Set yoghurt Greek yoghurt
Flavored yoghurt

12. Milk/skim milk
storage
Dry milk,
stabilizer, sugar
Standardizing tank
Homogenize at 60°C, 17Mpa
Heat treat at 97°C/10min.
Cool to 44°C
Blend in fermentation
tank at 44°C
Yoghurt
starter
Hold at 44°C to
pH 4.5
Cool to 4°C
yoghurt base
storage tank
Packaging filler
Casing/
palletizer
Blast cooler
Yoghurt-Store at
4°C
Production method of yogurt

13. Health Benefits of Yoghurt
Yoghurt is rich in essential
minerals like calcium that helps
strong bone - Prevent osteoporosis
The lactic acid of yoghurt
is a perfect medium to
maximize calcium
absorption
Strengthens and stabilize
the immune system
Yoghurt contains
Potassium helps in
Prevent high blood
pressure
May help you lose
weight -
yoghurt lost 81% more
than fat in the stomach
area
Rich source of
protein - Makes hair
healthy
Yoghurt which contains
probiotics as well as
calcium and vitamin D that
lower risk for colon cancer
Good bacteria called
probiotics in yoghurt
helps in digestion than
milk & Good for
digestive system

14. Curd
• Curd is a fermented dairy product obtained by coagulating milk in a process called curdling.
• Curd produce by milk of cow or buffalo.
• The coagulation can be caused by adding rennet or any edible acidic substance and then allowing it to sit.
• Milk that has been left to sour (added lactic acid bacteria) will also naturally produce curds.
• The liquid, which contains only whey proteins, is the whey.
• Bacteria used in making of curd is Lactobacillus.
• The bacterial culture converts milk to curd.
• This is achieved by the help of lactic acid bacteria.
• Lactobacillus can convert lactose into lactic acid, which imparts the sour taste to curd.
•When pasteurized milk is heated to a temperature of 30-40oC, or even at room temperature or refrigerator
temperature, and a small amount of old curd or whey added to it, the Lactobacillus in that curd or whey
sample starts to grow.
• Raw milk naturally contains Lactobacillus.

15. Production method of curd
Cooling and
storage 30-
40°C
Receiving
of milk
Preheating
(35-40°C)
Filtration/
clarification Standardization
Preheating
(60°C)
Homogenization
(175Kg/ cm²)
Heat
treatment
(90°C/10
min)
Cooling
(to 30°c)
Addition of Starter
cultures (1-1.5%)
Packaging Incubation
(30-37°C/6-8hr) Curd

16. Benefits of curd
Improves digestion
Improves bone strength
Enhances immunity
Effective hair care
Ensures brain health
Helps in weight reduction
Healthy heart
Makes skin healthy and shiny
Offers vaginal health
Stimulates appetite

17. Cheese
• Cheese is a dairy product, derived from milk and forms by coagulation of the milk protein casein.
• It comprises protein and fat from milk, usually the milk of cow, buffalo, goats or sheep. It takes about
ten pounds of milk to make one pounds of cheese.
• Besides the milk it contains a selected strain of bacteria, a milk clotting agent sodium chloride.
• Most cheeses are made with starter bacteria from the Lactococcus lactis, Streptococcus thermophilus,
Lactobacillus casei.
• Variations in the basic constituents, use of additional ingredient and different environmental
conditions surrounding the manufacture and subsequent ripening of cheese have given rise to various
verities of cheese.
• Cheese is packed with a very high concentration of essential nutrients including high quality proteins
and calcium. Cheese also contains phosphorous, zinc, vitamin A, riboflavin & vitamin B12

18. Types of cheese
Type Involved organisms Examples
Soft cheese Streptococcus cremoris, Penicillium camemberti Camembert, feta
Semi soft cheese Lactococcus lactis Gouda, port soft
Hard cheese Lactobacillus casei, Lactobacillus plantarum Mimolette, pelorina
Semi hard cheese Lactobacillus casei, Streptococcus cremoris Cheddar, cantal
Fresh cheese Streptococcus sp. Cottage cheese, mozzarella
Blue cheese Penicillium roqueforti, Lactococcus lactis Roquefort, stilton
Processes cheese Fungi or fungal spores used during ripening Gruyere, Colby
Semi-hard
cheese
Hard cheese
Semi-soft
cheese
Soft cheese Fresh cheese Blue cheese Processes
cheese

19. Production method of cheese
Pasteurized whole
cow’s milk (32°C)
0.01% CaCl₂ Starter culture
Acid
production
(32°C, 30 min)
Coagulation
(30°C, 40 min)
Cutting
(curd:1 cm³)
Cooking
(38°C, 40 min)
Whey
drainage
Mixing
Probiotic
culture
Whey
Pressing
(20°C,18h)
Brine salting
(15% NaCl,
20°C, 1h)
Vacuum
packaging
Storage
(4°C, 28 days)
Rennet

20. Strengthen immune system –
Some types of cheese help build a
strong Immune system to help
body fight infections & diseases
1
2
6
5
4
3
Helps reduce Migraine – Cheese is packed
with calcium and calcium intake reduces
migraine pain & attacks.
Great Sleep – Tryptophan and
amino acid found in cheese helps
reduce stress stimulate sleep
Prevent Osteoporosis – Cheese
contains of protein and calcium
Benefits of cheese
Health skin & Hair – great
source of Vitamin B and protein
Vitamin B in cheese reducing high
blood pressure

21. Kefir
• Kefir is a traditional fermented dairy product of middle east produce by milk of sheep, cow, goat or
mixed milk.
• It is beverage produced by the action of lactic acid bacteria, yeast and acetic acid bacteria on milk,
which produces a distinctive fermented milk product with unique properties.
• Used organisms Streptococcus lactis, Lecuconostoc sp., Saccharomyces, Lactobacillus kefiri.
• It is produced by adding a starter culture called “kefir grains” directly to milk. The kefir grains are a
mass of several different bacteria and yeasts embedded in a complex matrix of protein & carbohydrate.
• Kefir is a viscous, self carbonated beverage with smooth and whitish color having very small quantity
of alcohol.
• The mouth feel of kefir is described to be prickly & sparkly
• Characteristics of kefir,
Components 100g
Fat 3.5 - 3.8%
Protein 2.5 – 3.3%
Lactose 3 – 4%
Water 87-88%

22. Raw milk
Standardization
of fat (g/100g)
to 0.1-3.3
Warmed to
65°C,
homogenized
at 15MPa
Pasteurization
at 95 °C for
5min
Strained to remove
fermentate without
kefir grains
Kefir grains + milk
(incubated for 20-
24h & ripened for
7-8h at 10-12°C
Inoculation
at 20-25°C
with kefir
grains
Cooled to
20-25°C
Mother culture inoculated in fresh
milk to produce bulk starter
culture
Mass fermentation
18-24h at 20-25°C
Kefir – cooled &
stored at 4°C
Production method of kefir

23. Benefits of kefir
Helps restore a damaged gut Reduces cholesterol
Good for the skin
A natural antibiotic
Contains essential
nutrients
Suitable for lactose
intolerant
Improves bone density
Improves mood & reduces
anxiety
A good source of protein

24. • Churn buttermilk is the fluid remaining when the fat is removed by churning cream into butter.
• It is the watery end-product of butter making. But it has been replaced as a beverage by cultured butter
milk.
• Most modern buttermilk is cultured buttermilk, made from low-fat or skim milk and has less than 2% fat
and sometimes none.
• It is prepared from pasteurized skim or low-fat milk by fermented by a lactic culture and by aroma
producing bacteria.
•
• High-quality cultured buttermilk has mild acid flavor and a smooth viscous body and texture. Its
appearance is soft white,
Nutritional composition;(per 100ml)
•Rich in Vit.B 12, Potassium, Calcium, Riboflavin, Phosphorus, Zinc & Probiotics.
Water Protein Fat Ash Sugar
90.7 3.5 0.5 0.7 4.6
Cultured Butter Milk

25. Production method of Cultured Buttermilk
Receiving
skim milk
Filtration Pasteurization
(82-88°C/ 30 min)
Cooling
(22°C)
Inoculation
(1-2%)
Incubation
(21-22°C)
Coagulation
(12-16h)
Packaging
& Storage
(5-10°C)
Break-up of
coagulation
Cooling
(5-10°C)
Stater cultures of desirable bacteria
(Streptococcus lactis, Streptococcus
cremoris, Leuconostoc citrovorum, and
Leuconostoc dextranicum)

26. Benefits of Cultured Butter Milk
Responsible for healthy gastro-intestinal system.
Promotes nerve cell growth and
helps fight stress & anemia.
Boosts the body immune
system.
Responsible for bone health & to minimize the
blood pressure.

27.  It is a extremely viscous product with the flavor and aroma of butter milk. but with
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.
 It is consumed as a dressing of topping on other foods such as fruits.
Calories Phosphorus Calcium Vitamin B12 Carbohydrate Fat Vitamin B2
170 Kcal 31.14% 28.8% 28.85% 27.6% 12-30% 26.54%
 Nutritional composition;(per cup-240 ml)
Sour Cream

28. whole milk with cream (20% fat)
Heating (80°C/ 30min)
Homogenization 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
Production method of sour cream

29. Benefits of Sour Cream
Bone health Cardiac muscle health
Maintain cells Promotes growth

30. Kumiss
• Kumis is a type of fermented dairy product made from mare’s milk.
• Produced from a liquid starter culture.
• Kumis has a higher alcohol content than kefir.
• Mare’s milk contains less casein and fatty matter than cow’s milk.
• Production of higher carbon dioxide levels is also a characteristic of kumis.
• Acetic acid bacteria are not found in kumis.
• Kumis is dried and preserved for many seasons.
• Organism – Lactobacillus/Bacterium orienburgii, Lactobacillus bulgaricus, Lactobacillus bulgaricus,
Lactobacillus acidophilus, yeast
 Nutritional composition;(per 2 table teaspoons)
Lactic acid Alcohol Carbon dioxide Ethanol Lactose Fat Protein
0.7-1.8 % 1-2 % 0.5-0.9 % 1.3 % 2.3 % 1.5 % 2 %

31. Production method of Kumiss
Fresh mare’s milk
Heating (90°C – 92°C for 5 min)
Cooling at 27°C
Inoculation (Lactobacillus and yeast)
Incubation at 28°C (till acidity 0.7% - 0.8%)
Agitation (every 1- 2h)
Cooling and stirring (at 20°C)
Packaging
Storage (at 4°C for 24 h)

32. Benefits of Kumiss
 Rich in Antibiotics, vitamin A, B1, B2, B3, D, E and C
 Good in the case of emaciation and anemia.
 Develops immunity
 Beneficial for a range of chronic diseases.
 Influence on gastrointestinal tract
 Good for Cardiovascular system, Kidneys and Nervous
system.

33. Lassi
• Lassi is a ready-to-serve fermented milk beverage popular in India particularly in summer months.
• Good quality lassi should have creamy consistency, smooth texture, glossy sheen and white color with
yellowish tinge.
• Mild acidic flavor and sweetish taste of lassi make it a refreshing soft drink.
• It is flavored either with salt or sugar and other condiments or spices like ginger, coriander and mint
depending on regional preferences.
• Lassi is obtained from pasteurized whole milk or partly skim milk, cultured with lactic and aroma/flavor
producing organisms.
• Also a product prepared from cultured skim milk, commonly known as cultured butter milk is classified as
lassi.

34. Receiving
raw milk
Filtration &
heating (90°C) Cooling (60°C)
Homogenization
Cooling (40°C)
Production method of lassi
Addition of
culture at 2%
Incubation at 37°C
for 4 hours
Stirring with
lassi stirrer
Addition of color
& flavor
Packing Cooling (4°C)

35. Benefits of Lassi
Aids digestion
Prevents stomach problems
Rich in probiotics
Improves bone health
Boosts immunity
Good for skin

36. Acidophilus milk
• Typically a low fat or non fat milk to which active cultures of Lactobacillus acidophilus have been added.
• The milk can be refrigerated to prevent further growth of the harmless bacteria producing sweet acidophilus
milk.
• It can also be incubated at 38oC until a curd forms.
• Bifidobacterium bifidum may also be included.
Nutritional composition;(per cup-240ml)
Calories Fat Cholesterol Sodium Carbohydrates Protein Vitamin A Vitamin C Vitamin D Calcium
110 Kcal 4% 3% 5% 4% 16% 10% 2% 25% 30%

37. Production method of Acidophilus milk
Receiving milk (skim/ whole/ defatted)
Filtration/ clarification (35-40°C)
Homogenization
Sterilization (115°C/ 15min)
Cooling (38-40°C)
Incubation (38-40°C/ 12-16h)
Coagulation
Break-up of coagulum
Cooling (10°C)
Packaging & storage (5°C)

38. Benefits of Acidophilus milk
 Relieves from various gastrointestinal disorders.
 Possible improvement in immune status.
 Lower proliferation of cancerous cells.
 Possible lowering of blood cholesterol.

39. 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 Arab and North
Africa (Maghreb), buttermilk.
• There is a mixed microflora consisting of Streptococcus lactis, Streptococcus thermophilus, Lactobacillus
bulgaricus and Lactose fermenting yeasts.
• Leben has 7-10% fat.
• Many people who are lactose sensitive can still enjoy leben.
• In fact, leben contains lower amounts of lactose than milk and is easier to digest.
Nutritional composition; (per 100ml)
Energy Protein Fat Carbohydrates Calcium
64 Kcal 3 g 3.9 g 4.2 g 95 mg

40. Milk (in earthenware containers)
Inoculation with sample from previous batch
Incubation at ambient temperature until firm coagulation production
Churning with gradual addition of warm water
Addition of Fenugreek seed Butter (heating) Butter oil
Leben
Cooling
Packing
Production method of leben

41. Benefits of Leben
 Excellent source of Calcium, Vitamin D and high quality protein.
 Maintains the balance of bacteria necessary for a healthy digestive system.
 Boosts the immune system
 Significant source of Magnesium, Potassium, Phosphorous, Riboflavin, Iodine, Zinc, Vitamin B12 and
B6

42. Conclusion
 Fermented dairy products are widely consumed worldwide and they have shown a
substantial consumption increase in recent years.
 There is a growing consumer interest in fermented dairy products due to the nutritional
& health benefits offered by these products because their effect on the bacterial
microbiota of the intestine contributes to a healthy life and to increase in life
expectancy.
 Many fermented dairy products contains probiotics & prebiotics which have sparked
the interest of the dairy industry due to scientific evidence related to their positive
health benefits.