Microbiology of Dairy Products

Teacher

Dr. Rajashree Jena

Category

Core Courses

Course Attendees

Still no participant

Course Reviews

Still no reviews

Course Name : Microbiology of Dairy Products

Code (Credit) : CUTM1151 (1-1-0)

Course Objectives

  • To educate students about the microorganisms and their significance associated with different dairy products.
  • Imparting knowledge on different microbial associated defects of the products.
  • To disseminate recent information on microbiological standards and biopreservation of dairy products.

Learning Outcomes

  • Acquire knowledge on micro-environment of different indigenous dairy products.
  • Explain the public health significance of various dairy products.
  • Implement the packaging concepts in dairy industry to avoid spoilage and enhance shelf-life of dairy products.

Course Syllabus

Module-I: Microbiology of Cream and Butter (3 hrs)

  • Micro-environment and impact of critical process factors on entry of spoilage and pathogenic organisms in cream and butter; Microbiological aspects including defects in pasteurized (ripened/ unripened cream), sterilized and UHT cream.
  • Micro-environment and impact of critical process factors on entry of spoilage and pathogenic organisms in butter
  • Factors influencing the microbial growth during batch/continuous butter making process; Microbial Defects in butter - Bacterial/mold discoloration, enzymatic deterioration and their control measures; Regulatory microbiological standards.

Practice (4 hrs):

  • Microbiological examination of raw and pasteurized cream for Standard plate count (SPC), coliform counts direct microscopic count (DMC), lipolytic, proteolytic counts and dye reduction tests.
  • Microbiological examination of salted and unsalted butter for SPC, coliforms, yeast and mold count, psychrotrophic, lipolytic and proteolytic counts.

Module-II: Microbiology of Condensed, Evaporated and Dried Products (3 hrs)

  • Type of microorganisms associated with condensed and evaporated milks, their growth/ survival during manufacture and storage.
  • Microbial defects - Bacterial thickening / Mold button formation in SCM; Gassiness/bloating, Bacterial coagulation (Sour and sweet), Bitterness, Fishy flavor in evaporated milk.
  • Pre-heating/DSI temperature and their impact on microflora of dried products; Effect of reconstitution on microbial quality of milk powder including baby foods and survivability of pathogens; Regulatory microbiological standards.

Practice (3 hrs):

  • Microbiological examination of concentrated milk for SPC, coliforms, yeast and mold counts, thermoduric, thermophilic and spore counts.
  • Microbiological examination of dried milks for SPC, coliforms, S. aureus, B. cereus, E. coli, Salmonella

Module-III: Microbiology of Ice Cream and Indigenous Milk Products (2 hrs)

  • Microenvironment in ice cream, microbiological quality of ingredients, critical process factors and their impact on entry of pathogens in ice cream and frozen desserts, their survival during storage, food poisoning out breaks and legal standards.
  • Microbiology of Indigenous Milk Products: Predominance of spoilage and pathogenic organisms in khoa and khoa based sweets – burfi, peda, gulabjamun, etc., paneer, Chhanna and Chhanna based sweets – rasogulla; kheer, shrikhand, dahi, kulfi etc.

Practice (4 hrs):

  • Microbiological examination of ice-cream and other frozen desserts for SPC, coliforms, Staphylococcal counts, Salmonella.
  • Microbiological examination of khoa for SPC, coliforms and staphylococcal counts besides yeast and mold counts.
  • Microbiological examination of paneer and shrikhand for SPC, coliforms, yeast and molds and Staphylococcal counts.

Module-IV: Microbial Safety and Packaging (3 hrs)

  • Factors affecting the microbiological quality in reference to production, processing, storage and distribution.
  • Microbial safety in relation to potential pathogens and their public health significance.
  • Active packaging concepts and role in bio-preservation.

Practice (1 hr):

  • Microbiological examination of packaging materials for SPC and yeast and mold counts.

Suggested Readings:

 

Text Books

  • Robinson, R.K. 2002. Dairy Microbiology Handbook - The Microbiology of Milk and Milk Products. 3rd ed. Wiley-Interscience, New York.
  • Marth E.H. & Steele J. 1998. Applied Dairy Microbiology- 2nd ed. Taylor and Francis, New York.
  • Varnam, A.H. and Sutherland, J.P. 1994. Milk and Milk Products: Technology, Chemistry and Microbiology, Vol. I, Food Products Series. Chapman and Hall, London.

Online Sources

Session Plan

Session 1

Micro-environment and microbiological defects in pasteurized (ripened/ unripened cream), sterilized and UHT cream (1 hr).

Session 2 (Practice)

Microbiological examination of raw and pasteurized cream for Standard plate count (SPC), coliform counts direct microscopic count (DMC), lipolytic, proteolytic counts and dye reduction tests (2 hrs).

Session 3

Micro-environment and entry of spoilage and pathogenic organisms in butter (1 hr).

Session 4 (Practice)

Microbiological examination of salted and unsalted butter for SPC, coliforms, yeast and mold count, psychrotrophic, lipolytic and proteolytic counts (2 hrs).

Session 5

Microbial growth during batch/continuous butter making process and microbial defects in butter; Regulatory microbiological standards (1 hr).

Session 6

Microenvironment of condensed and evaporated milks, their growth/ survival during manufacture and storage (1 hr).

Session 7 (Practice)

Microbiological examination of concentrated milk for SPC, coliforms, yeast and mold counts, thermoduric, thermophilic and spore counts (1.5 hrs).

Session 8

Microbial defects - Bacterial thickening / Mold button formation in SCM; Gassiness/bloating, Bacterial coagulation (Sour and sweet), Bitterness, Fishy flavor in evaporated milk (1 hr).

Session 9

Microflora of dried products; Effect of reconstitution on microbial quality of milk powder including baby foods and survivability of pathogens; Regulatory microbiological standards (1 hr).

Session 10 (Practice)

Microbiological examination of dried milks for SPC, coliforms, S. aureus, B. cereus, E. coli, Salmonella (1.5 hrs).

Session 11

Microenvironment in ice cream and frozen desserts, their survival during storage, food poisoning out breaks and legal standards (1 hr).

Session 12 (Practice)

Microbiological examination of ice-cream and other frozen desserts for SPC, coliforms, Staphylococcal counts, Salmonella (1.5 hrs).

Session 13

Predominance of spoilage and pathogenic organisms in khoa and khoa based sweets – burfi, peda, gulabjamun, etc., and paneer, Chhanna and Chhanna based sweets–rasogulla; kheer, shrikhand, dahi, kulfi etc (1 hr).

Session 14 (Practice)

Microbiological examination of khoa for SPC, coliforms and staphylococcal counts besides yeast and mold counts (1 hr).

Session 15 (Practice)

Microbiological examination of paneer and shrikhand for SPC, spores, coliforms, yeast and mold count and Staphylococcal counts (1.5 hrs).

Session 16

Factors affecting the microbiological quality in reference to production, processing, storage and distribution (1 hr).

Session 17

Microbial safety in relation to potential pathogens and their public health significance (1 hr).

Session 18

Active packaging concepts and role in bio-preservation (1 hr).

Session 19 (Practice)

Microbiological examination of packaging materials for SPC, Spores and Yeast and mold counts (1 hr).

Our Main Teachers

Dr. Rajashree Jena is currently working as Assistant Professor in the Department of Dairy Technology, Centurion University of Technology and Management, Paralakhemundi Campus, Odisha. She has obtained her Ph. D degree from National Dairy Research Institute, Karnal in the field of Dairy Microbiology. She has more than 3 years of research and teaching experience at […]