TECHNOLOGY OF MILK
Learning outcomes of the course unit
- Learn the organisational and technical actions necessary for informed management of production lines for milk for direct consumption and for fermented milk.
- Study in depth, especially on a practical level, systems of running plants for heat treatment aimed at obtaining fixed bacterial reductions for minimal heat damage to nutritional and organoleptic properties.
- Study in depth the knowledge on plant and equipment necessary for production, in particular: health and hygiene aspects, prevention of bacterial pollution, criteria for choosing the type of equipment in order to optimise the quality of the various products.
- Application of microbial ecology knowledge for diagnosing and preventing production anomalies (in particular, bacterial pollution in long life products).
- Practical aspects and behaviour in the phases of production of various types of fermented milk.
The course requires good knowledge of some basic disciplines such as, chemistry, physics, technical physics and microbiology. Chemistry is useful for describing the nutritional aspects of milk and its by-products as well as understanding the analytical activities necessary for qualifying the products, also from a legal point of view. Knowledge of physics and technical physics is necessary for defining the operating problems of various plants and for understanding their construction methods and fields of application. Microbiology is essential from the regulation point of view (product hygiene) and also for defining the technological problems connected with hygiene and health aspects of products and plants. Under this light, microbial ecology plays an essential role in the diagnosis of the causes of a production anomaly. Ecology requires a good general microbiology approach.
Course contents summary
- Quality testing
- Raw milk reception and storage.
- Milk pasteurization
- Extended-life pasteurized milk
- Long life milk (autoclave treatments and direct and indirect UHT)
- Centrifuge separators
- Continuous milk cleaning
- Continuous skimming
- The homogeniser and its main components
- Energy aspects.
- Air and gas in milk
- Vacuum treatment.
MILK TRANSFER WITH PUMPS
- Centrifugal pumps
- Liquid ring pumps
- Positive pumps
- Pipes (welds and connections)
- Agitation in tanks
- Buffer tanks
MANAGEMENT OF A PROCESS LINE
- General details
- Pasteurized milk production
- Sterile milk production
CAUSES OF POLLUTION
- How to diagnose the causes of pollution
- Pollution prevention
- Investigation techniques in the event of pollution
Fermented milk production
- Preparation of starters
- General requirements for fermented milk preparation
- Yoghurt production technology
- Yoghurt production plant
- Various types of yoghurt
- Other fermented milks (general details)
- The various systems
- Structure of the machines
- Management of the machines
- Most frequent causes of microbial pollution.
Dairy Processing Handbook, Tetra Pak Processing Systems (LUND- SWEDEN) (1995),
- Microbial Ecology of Foods Vol 1, Academic Press, New York,1980
- prof. Claudio Salvadori's personal lecture notes.
24 oral lectures with the aid of numerous colour pictures showing the layout of plants and the detail of individual components.
A few hours are also dedicated to guided tours of production plants with viewing of the parts and various mechanisms
Examinations are mainly oral, possibly with calculations to be carried out during exposition of the various topics.