FST 256/6303  TECHNOLOGY OF FOOD PRESERVATION

 

Unit I (6 Lectures)

Historical development and current trends; Introduction to food technology; Food attributes- colour, texture, flavour, nutritive value and consumer preference.

Post harvest losses due to physical, chemical & microbial changes and their control measures.

Principles and methods of food preservation.  

 

Unit II (10 Lectures)

Thermal processing of food: principle, advantage and disadvantages; Pasteurization, sterilization, commercial sterilization and blanching. Thermal resistance of microorganism and enzymes. Heat penetration studies. Time temperature combination .D-value, F-value, Z-value. Canning technology.  

 

Unit III (8 Lectures)

Low temperature preservation : refrigeration and freezing, advantages and disadvantages; Types of refrigerants, requirement for cold storage. Temperature requirement for the growth of microbes. Freezing point, freezing time, freezing rate, thermal arrest time. Food group based on freezing rate. Mechanism of freezing. Factors affecting freezing rate.

Thawing, Cryogenic freezing.

 

 Unit IV (8 Lectures)

Drying and Dehydration: Concept of water activity,

Methods of drying, Process of drying. Factors affecting drying rate. Physico-chemical changes during drying, Advantages and disadvantages of drying.

Rehydration and coefficient of rehydration.  

 

Unit V (9 Lectures)

Radiation preservation - mechanism, unit of radio-activity, radappertization, radurization, radicidation. Dose requiremenT for various foods, public health aspects of irradiated food. Dosimetry.

Microwave heating :principle and applications.

Chemical Preservation : Preservation by using additives, chemicals, antibiotics, sugar, salt and smoking.  

References