This presentation gives you the overall information of how enzymes are used in dairy industry and detailed explanation on production of cheese. Refer to the references for more detailed information.
2. Contents
➢ Introduction
➢ Use of enzymes
➢ Dairy products
➢ Cheese and Types
➢ Production of cheese
➢ Equipments
➢ Purification of Chymosin
➢ Byproducts and their uses
➢ Conclusion
➢ Future Scope
➢ References
3. Introduction
● An enzyme is a protein formed by the body that acts as a catalyst to cause a certain desired
reaction.
● Enzymes are very specific.Each enzyme is designed to initiate a specific response with a specific
result. There are many enzymes in the human body.
● Dairy products, milk products or lacticinia are a type of food produced from or containing the milk
of mammals, primarily cattle,goats, sheep, camels etc
● Dairy enzymes are enzymes used for the production of cheese and yoghurt as well as other milk
products.
Enzyme Uses
Lactase Hydrolyses lactose to glucose and galactose
Protease Denaturing Whey proteins
Rennin Solidifies milk proteins
Lipase Ripening of cheese
4. Enzymes used in Dairy Industry
● Rennet: Rennet and rennin are general terms for any enzyme used to coagulate milk. The
most common enzyme isolated from rennet is chymosin.Bioengineered chymosin may be
involved in the production of up to 70% of cheese products.
● Proteases: Cow milk also contains whey proteins such as lactalbumin and lactoglobulin. The
denaturing of these whey proteins, using proteases, results in a creamier yogurt product.
● Lactase: Lactase is a glycoside hydrolase enzyme that cuts lactose into its constituent
sugars, galactose, and glucose.Lactase is used commercially to prepare lactose-free
products.It is also used in the preparation of ice cream, to make a creamier and sweeter
tasting product.
● Lipases: Lipases are used to break down milk fats and give characteristic flavors to cheeses.
Animal lipases are obtained from kid, calf, and lamb, while microbial lipase is derived by
fermentation with the fungal species Mucor miehei.
6. Cheese
● Cheese is a milk concentrate, the basic solids of which consist mainly of protein
(actually casein) and fat.
● The casein and fat in the milk are concentrated approximately 10 times in
production of hard and some semi-hard types of cheese.
● Cheese can be made using pasteurized or raw milk.
● Cheese made from raw milk imparts different flavors and texture characteristics
to the finished cheese.
● For some cheese varieties, raw milk is given a mild heat treatment (below
pasteurization) prior to cheese making to destroy some of the spoilage
organisms and provide better conditions for the cheese cultures.
7. Types of cheese
● Cheese can be broadly categorized as acid or rennet cheese, and natural or
process cheeses.
● Acid cheeses are made by adding acid to the milk to cause the proteins to
coagulate.
● Fresh cheeses, such as cream cheese or queso fresco, are made by direct
acidification.
● Most types of cheese, such as cheddar or Swiss, use rennet (an enzyme) in
addition to the starter cultures to coagulate the milk.
● The term “natural cheese” is an industry term referring to cheese that is made
directly from milk.
● Process cheese is made using natural cheese plus other ingredients that are
cooked together to change the textural and/or melting properties and increase
shelf life.
8. Production of cheese
Ingredients
● The main ingredient in cheese is milk. Cheese is made using cow, goat, sheep, water buffalo or a blend of these milks.
● The type of coagulant used depends on the type of cheese desired.
● For acid cheeses, an acid source such as acetic acid (the acid in vinegar) or gluconodelta-lactone (a mild food acid) is used.
● For rennet cheeses, calf rennet or, more commonly, a rennet produced through microbial bioprocessing is used.
● Calcium chloride is sometimes added to the cheese to improve the coagulation properties of the milk.Flavorings may be added
depending on the cheese. Some common ingredients include herbs, spices, hot and sweet peppers, horseradish, and port wine
Bacterial Cultures
● Cultures for cheese making are called lactic acid bacteria (LAB) because their primary source of energy is the lactose in milk
and their primary metabolic product is lactic acid.
● There is a wide variety of bacterial cultures available that provide distinct flavor and textural characteristics to cheeses.
● Starter cultures are used early in the cheese making process to assist with coagulation by lowering the pH prior to rennet
addition.Typical starter bacteria include Lactococcus lactis subsp. lactis or cremoris, Streptococcus salivarius subsp.
Thermophilus.
● Adjunct cultures are used to provide or enhance the characteristic flavors and textures of cheese. Common adjunct cultures
added during manufacture include Lactobacillus casei and Lactobacillus plantarum for flavor in Cheddar cheese
● Yeasts and molds are used in some cheeses to provide the characteristic colors and flavors of some cheese varieties
10. General Manufacturing process
The steps involved in cheese making are:
● Standardize Milk
● Pasteurize/Heat Treat Milk
● Cool Milk
● Inoculate with Starter & Non-Starter Bacteria and Ripen
● Add Rennet and Form Curd
● Cut Curd and Heat
● Drain Whey
● Cheddaring
● Dry Salt or Brine
● Form Cheese into Blocks
● Store and Age
● Package
12. Extraction and Purification of Chymosin(Rennet)
The steps involved were:
● Extraction of enzyme from abomasal tissue
● Clarification of tissue extracts
● Precipitation
● Dialysis
● DEAE cellulose ion exchange chromatography
● Gel filtration chromatography
13. Key Points
Pasteurization conditions used for milk :
Refrigerated milk - 63 degree celsius for 30 minutes (Batch process)
Refrigerated milk- 72 degree celsius for 15 seconds(Continuous HTST)
Refrigerated extended storage milk- 138 degrees for 2 seconds(continuous ultra
pasteurization)
Mechanical reduction of bacteria :Spore and bacteria removing separators and
Microfiltration.
15. Byproducts - Whey
● Whey is the watery liquid that remains after the coagulation of the casein
proteins in cheesemaking.
● Whey contains most of the lactose and about 20% of the protein in milk.
● Cheesemaking generates large volumes of whey. About 80% of the volume of
milk used to make cheese remains as whey.
Traditionally, cheesemakers considered whey a waste product and looked for the
most economical way to dispose of it. Generally, they discarded it in one of three
ways:
● Discharged into waterways.
● Sprayed onto farmland.
● Sold for a low return as animal feed.
16. Uses of Whey
● Whey is highly valued for its nutritional benefits, particularly whey protein. This is a rich
source of essential amino acids – the building blocks of muscles and other human tissues.
● Whey proteins are also easily digested and quickly absorbed by the body. These properties
make them valuable ingredients in products for health and wellbeing.
● It is helpful in enhancing athletic performance and improving recovery from exercise.
● Whey products are also known for their functional properties. This makes them a valuable
ingredient in formulating food products with benefits including improving flavour and texture
and increasing yield.
1. Emulsification - Creates stable emulsions and prevents fat globules from forming clumps.
2. Flavour enhancement-Brings out already present flavours or adds flavour.
3. Gelling and heat setting-Maintains moistness and improves texture and mouth feel.
4. Whipping, foaming and aeration-Maintains foam properties, enhancing appearance, taste
and texture.
● Whey can also be processed into ethanol, which is used in pharmaceuticals, perfumes, inks
and alcoholic beverages
17. Conclusion
● The global market for the production of microbial enzymes for use in
dairy-products manufacture is considerably large, but is being
dominated only by a limited number of enzyme producers.
● In India the microbial dairy enzymes requirement has been very
limited till now.
● However, with the advent of technological processes for the
manufacture of different varieties of milk products, such as cheeses
by the State Dairy Federations, Co-operatives and Private Dairy
Product Manufacturers like Amul, Vijaya, Verka, Dynamix, Nestle,
Smith Kline, etc., the markets for the sale of such products in
megacities and towns has been slowly growing for the past two to
three years.
18. Future scope
● Presently, many of these microbial enzymes, such as
microbial rennets and other enzymes are being imported.
● Hence, there is a scope for the production of enzymes
such as microbial rennet, lactase, proteinases, and
lipases indigenously.
● In the near future, the requirement for these enzymes is
bound to increase by leaps and bounds, basically due to
requirement of value-added dairy products in the country.
19. References
● Mohanty, A., Mukhopadhyay, U., Kaushik, J., Grover, S., & Batish, V. (2003).
Isolation, purification and characterization of chymosin from riverine buffalo
(Bubalos bubalis). Journal of Dairy Research, 70(1), 37-43.
doi:10.1017/S0022029902005927
● http://www.allresearchjournal.com/archives/2015/vol1issue10/PartH/1-9-198
● http://www.agrometal.hu/english/dairy_plants/equipments/
● http://dairyprocessinghandbook.com/chapter/cheese
● Gurung N, Ray S, Bose S, Rai V. A Broader View: Microbial Enzymes and
Their Relevance in Industries, Medicine, and Beyond. BioMed Research
International. 2013;2013:329121. doi:10.1155/2013/329121.
● https://www.sciencelearn.org.nz/resources/832-uses-of-whey
● http://www.milkfacts.info/Milk%20Processing/Heat%20Treatments%20and%2
0Pasteurization