Learning Outcomes
The objectives of this course is to familiarize students with laboratory testing of milk and dairy products by performing microbiological and chemical analyses on real foods, obtaining and interpreting the results. In particular, upon successful attendance and examination, the student is expected to know the sampling plans for milk and dairy products according to Reg. 2073/2005, the common microbiological methods for assessing the quality of milk and dairy products, and the chemical methods for assessing the quality of milk and the evaluation of the level of heat treatment of milk.
Course Content (Syllabus)
3 hours: Guided tour of the lab and Laboratory Safety rules. Sampling of milk and milk products: General requirements, equipment and methods of sampling. Two- and three-class sampling plans. Regulation (EC) No 2073/2005 on microbiological criteria for foodstuffs.
3 hours: Milk Pasteurization. Enumeration of the Total Plate Count of Milk (ISO 4833-1:2013). Methylene Blue Reduction Test.
3 hours: Enumeration of Eterobacteriacae (ISO 21528-2:2004) and coagulase-positive Staphylococci (ISO 6888-1:1999). Yogurt manufacture.
3 hours: Isolation of selected milk microorganisms. Enumeration of Enterobacteriacae with the Most Probable Number (MPN) method (ISO 21528-1:2004). Determination of the pH of yogurt.
3 hours: Recording and evaluating the results of microbiological analyses of milk. Enumeration of Lactobacillus spp. in yogurt (ISO 7889:2003).
3 hours: Determination of the titratable acidity of milk. Phosphatase test. Peroxidase test.
3 hours: Determination of the fat content of milk. Determination of the specific gravity, the total solids and the total solids non fat of milk.
3 hours: Detection and quantitation of milk adulteration.
3 hours: Recording and evaluating the results of microbiological analyses of yogurt. Staining (Methylene Blue, Gram) and microscopic observation of milk and yogurt microorganisms. Biochemical identification tests.
3 hours: HACCP implementation in the manufacture of dairy products (in-class exercise). Recap of the lab.