Dairy science and technology

MAJOR SUBJECT GROUP - DAIRY SCIENCE

(Sub-Subjects: 17.1: Dairy Microbiology, 17.2: Dairy Chemistry)

Unit-I: 

Chemical composition of various food of plant and animal origin, structure and functions of food constituents, additives, preservatives, flavours and antioxidants, composition and physico-chemical and nutritional properties of milk and colostrum, chemistry of milk, constituents, nutrients and milk products. Test for the quality of milk, butter, ghee, milk powder etc., adulterants, neutralizers and preservatives, their detection, heat stability of milk.

Unit II: 

Introduction to dairy microbiology – Milk production hygiene and critical risk factors affecting microbiological quality on-farm; Microorganisms associated with milk and their classification based on growth temperature– psychrotrophs, mesophiles, thermodurics and thermophiles; Microbial metabolites and their role in spoilages- souring, curdling, gassiness, ropiness, proteolysis, lipolysis, abnormal flavour and colour; Antimicrobial systems in raw milk; Microbiological grading of raw milk; Microflora of mastitic milk and its importance in dairy industry; Food poisoning, food infections, toxi-infections and other milk borne diseases and their control.

Unit-III: 

Composition and chemistry of cream, butter, ghee, ice-cream, cheese, condensed and dried milks, infant food, spoilage of ghee and use of antioxidants, chemistry of milk fermentation, chemistry of rennin coagulation of milk and changes occurring during ripening of cheese, physico-chemical changes in the manufacture and storage of milk powder, lactose, crystallization and its significance, physicochemical changes during the manufacture of indigenous milk products, quality standards of dairy products.

Unit IV: 

Bacteriological aspects of milk processing - Thermization, pasteurization, boiling, sterilization, UHT, bactofugation, and membrane filtration; Microbiological quality of cream, butter, ice-cream, concentrated dairy products, dried milks, infants milk foods, indigenous dairy products; Factors affecting the microbiological quality of these products during production, processing, handling, storage and distribution; Enumeration, isolation and identification of conventional and emerging dairy pathogens, detection of microbial toxins, drug residues in milk and their public health importance; Microbial defects associated with dairy products and their control; Microbiology of dairy starters; Classification, genetic aspects and carbohydrate metabolism of Lactic Acid Bacteria (LAB); Preservation, propagation and quality control of dairy starters and their inhibition by antibiotic residues, detergents, sanitizers, bacteriophages etc.; Microbiology of fermented milks, cheeses and application of probiotic concept in dahi, yoghurt, Kefir, Kumiss, Bulgarian milk, cultured buttermilk, leben,yakult, cheddar and processed cheese; Dairy plant hygiene and sanitation - Microbiology of air, water, equipments, packaging materials, personnel, disposal of dairy waste; Microbiological standards for milk and milk products - PFA, BIS, Codex/ ISO standards (ISO 9001: 2001/ISO 22000:2005).

MAJOR SUBJECT GROUP - DAIRY TECHNOLOGY

(Sub-Subjects: 18.1: Dairy Technology, 18.2: Dairy Engineering)

UNIT-I: 

Principles and processes of food preservation, non-conventional sources, processing of fluid milk, Computerization and Automatic Process Controls in Milk Processing. HACCP Concepts in Fluid Milk Processing. Advances in Centrifugal Separation and Bactofugation. Manufacture of various types of dairy products and changes occurring during manufacture and storage and their defects. Sensory evaluation and judging of milk and milk products, types of packaging materials and their properties, packing forms and operations, problems in food packaging, recent advances in packaging dairy and food products. Intelligent Food Packaging. Nutritional Labeling of Food Products. Application of Membrane Processing in Milk Processing.

UNIT-II: 

Materials and sanitary features of the dairy equipments. Homogenizer- Theory of Homogenization. Triplex pump, Lubrication of the Homogenizer, care and Management of homogenizer, Homogenizer Accessories and Standards for Homogenizer. Pasteurizer- Pasteurizer construction & Principle Materials used in Construction of Pasteurizers. High temperature short time Pasteurizer, care of Pasteurizer, Reaction Kinetics, Sterilizer, Mixing & agitation equipments, principles of evaporation, drying. Atmosphere concentration, Vacuum Pan, Fluidization. Care of Vacuum Pan, Atmospheric Drum Dryer. Spray Dryer principles of dairy plant layout and design, Functional Design, space requirement of Milk Plant, problem through computers, centralized dispersal of data processing, d- BASE-III, Lotus 1-2-3 to graphics, Fortran.

UNIT-III:

 Fluid mechanics- properties of fluids, Bernoulli’s equation and its applications, hydraulic systems Types of Pumps, Sanitary pumps, Standards for Centrifugal and Positive Rotatory Type of pumps, Selection of Pumps. Care and Upkeep of Pumps dimensional analysis, refrigeration and air-conditioning. Artificial Refrigeration, Compression Refrigeration System, Refrigeration Accessories. Calculation of size of Refrigeration Machine Requirements. Heat-transfer and thermodynamics; mechanical separations, Rittinger’s and Kick’s laws, Engineering of mechanics, theory of machine, strength of materials, Hook’s law, materials of fabrications, machine tools, Electrical Engg., Electromagnetic induction, Magnetic- Hysteresis loop (BH Curve), AC fundamentals.