Dairy Microbiology

Course content

The course will contain lectures on:

  • Raw milk microflora
  • Sweet dairy products microflora
  • Pathogenic and spoilage microflora
  • Primary (lactic acid bacteria) and secondary (yeasts, moulds, propionibacterium, red smear microflora, lactic acid bacteria ripening cultures) starter cultures microflora
  • Bacteriophage and bacteriophage resistance
  • Role of starter culture physiology on growth and end products (aroma formation, proteolysis, glycolysis, amino acid catabolism)
  • Non-starter lactic acid bacteria, adjunct cultures and their role in cheese ripening

Laboratory and theoretical excercises will include:

  • Raw milk microflora
  • Characterization of starter cultures using culture and culture independent techniques
  • Detection and propagation of bacteriophages from dairy products
  • Influence of starter culture propagation conditions on starter composition and activity

An excursion to a starter culture company will be included.


MSc Programme in Food Science and Technology

Learning outcome

The aim of the course is to give the students a thorough knowledge of raw milk microflora, and microflora in sweet milk products as well as on microflora in starter cultures. Focus will be on primary and secondary starter cultures for dairy products, including the adventious microflora associated with cheese.

Through lectures and laboratory exercies the course will also give the students additional knowledge on microbiological analysis on organisms relevant for dairy products. Knowledge of the most important spoilage and patogens in dairy products has also been obtained.
After completing the course the student should be able to:


  • Describe the composition of starter cultures and their use in dairy products
  • Describe the secondary, adjunct and adventious microflora found in cheese and their biochemical role in cheese ripening
  • Comprehend the role of physiology of starter, secondary starter, adjunct cultures and non-starter bacteria in fermented dairy products
  • Comprehend the principles for starter production
  • Comprehend how bacteriophages influence fermented dairy product quality and how to detect them
  • Display knowledge on culture dependent and culture independent techniqes for quantification of microorganisms from dairy products


  • Apply principles for species and strain identification of dairy organisms
  • Analyse dairy product for relevant microorganisms using classical and molecular biology based methods and evaluate the putative source of them
  • Compare literature information with own obtained data


  • Find, use and evaluate dairy microbiology literature in relation to dairy fermentation processes
  • Cooperate with fellow students about literature and practical laboratory work
  • Communicate and evaluate own data in relation to literature in writing and orally

Lectures, theoretical and practical exercises, E-learning as well as one excursion.

See Absalon for a list of course literature. It will include textbooks, reviews and original litterature, presentations, notes and laboratory manuals.




Qualifications within the field of microbiology of fermented food and beverages are recommended.

Academic qualifications equivalent to a BSc degree is recommended.

Continuous feedback during the course of the semester
7,5 ECTS
Type of assessment
Oral examination, 20 min
Type of assessment details
Individual oral examination without time for preparation. 3 weeks before the examination, all examination questions (covering the essential issues of the course) are handed out. At the examination, general knowledge within starter and non-starter cultures and adventitious microflora (including patogens and spoilage microorganisms and bacteriophages), will be tested.
All aids allowed
Marking scale
7-point grading scale
Censorship form
No external censorship
Exam period

Several internal examiners


Same as ordinary exam

Criteria for exam assessment

See Learning Outcome.

Single subject courses (day)

  • Category
  • Hours
  • Lectures
  • 28
  • Preparation
  • 74
  • Theory exercises
  • 25
  • Practical exercises
  • 50
  • Excursions
  • 6
  • Guidance
  • 10
  • Exam Preparation
  • 12
  • Exam
  • 1
  • English
  • 206


Course number
7,5 ECTS
Programme level
Full Degree Master

1 block

Block 2
The number of seats may be reduced in the late registration period
Study Board of Food, Human Nutrition and Sports
Contracting department
  • Department of Food Science
Contracting faculty
  • Faculty of Science
Course Coordinators
  • Paulina Deptula   (7-696a75797a7166456b74746933707a336970)
  • Henrik Siegumfeldt   (6-776d696b7971446a737368326f7932686f)

Various from KU FOOD.

Saved on the 28-02-2023

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