During the manufacture of different dairy products, the inevitable problem of utilization of by-products is encountered. Because of their unique and important nutrients available in the by-products, they have to be utilized in a proper manner considering the welfare of the general masses.

*The by-products obtained from dairy industry are as follows: *

1. Skim milk:

• Flavoured milk is prepared by Pasteurization method.
• Sterilized flavoured milk is prepared by Sterilization Method.
• Cultured Buttermilk is obtained from Fermentation
• Concentrated sour skim milk is prepared from Fermentation and Concentration
• Plain and Sweetened Condensed skim milk obtained from Concentration
• Dried skim milk or Skim milk powder or Non Fat Dry Milk NFDM) from Drying
• Cottage cheese is obtained from Coagulation

2. Buttermilk

• Condensed buttermilk by Fermentation and Concentration.
• Dried buttermilk by Concentration and drying.
• Soft cheese by Coagulation

3. Whey

• Whey beverage, Yeast whey prepared by Fermentation

• Plain and sweetened condensed whey, whey protein concentrate, whey paste, lactose can be obtained by process of Concentration

• Dried whey is obtained by Drying

• Ricotta cheese by Coagulation

4.Ghee residue

Sweetmeat, Toffee, Sweet paste is done by Processing.

The Process of Pasteurization:

According to International Dairy Federation (IDF), pasteurization can be defined as ‘a process applied to a product with the object of minimizing possible health hazards arising from pathogenic microorganisms associated with milk by heat treatment, which is consistent with minimal chemical, physical and sensory changes in the product’.

In general, the term pasteurization as applied to market milk refers to the process of heating every particle of milk to at least 63°C for 30 min or 72°C for 15s or to any temperature-time combination which is equally efficient, in a properly operated equipment. After pasteurization, the milk is immediately cooled to 5°C or below.

Importance of Pasteurization are : To render milk safe for human consumption by destroying all the pathogenic microorganisms and To improve the keeping quality of milk by killing almost all spoilage organisms (88-99%).