Microbiology of processed foods
Learning outcomes of the course unit
The course aims to know the biological phenomena behind the use of virtuous microorganisms for the production of the main fermented foods. The knowledge of the principles of food processing obtained by fermentation will allow the student to understand the concepts of the interactions which occur between process technology and microorganisms used in the production of fermented foods healthy and of high quality.
The course aims to put the student in a position to draw conclusions about the effect of the presence and the development of microorganisms responsible for the good characteristics of fermented food in agreement with the objectives defined in the Master and in agreement with the area of food microbiology
aspects of general and food microbiology
Course contents summary
The first lessons are about general aspect relating to spontaneous or guided fermentation as food processing method.
The second part of the course covers the knowledge of the main players of the microbial fermentation: lactic acid bacteria and yeasts. In particular their use as natural or selected starter and their significance in the typical and autoctonus character of a fermented food are considered.
The third part of the course deals with the basic principles of microbial growth related to production of the main fermented foods of animal and vegetable origin and the microbial origin of same organoleptic characteristics
Food processing: from raw material to ready-to-consumer food
Microbiological aspect determining the processing of raw materials in fermented foods
Presence of microorganisms in fermented foods: lactic acid bacteria, yeasts, natural and selected starters
Microbial aspects in dairy products: microorganisms of yogurt and fermented milk, cheese: significance of the microorganism at various stages of production, microorganisms characteristic of some types of cheese
The role of microorganisms for the production of salami: Factors conditioning Micrococcacee of microbial growth, lactic acid bacteria and mold; The natural fermentation and ripening
The role of microorganisms for bread production. Fermentation and substrate fermentation. Yeast; Microbial ecology of sourdoughs
The role of microorganisms in the winemaking process: The wine yeasts and alcoholic fermentation. Lactic acid bacteria: the defects and the malolactic fermentation. Role of microorganisms in the production of special wines (vini novelli, sweet wines, sparkling wine or champagne, fortified wines)
The role of microorganisms in beer production: the possible microbial contamination and hygiene problems in the early stages of malting and mashing, fermentation and starter cultures
The role of microorganisms in the production of vinegar: acetic acid bacteria in wine and vinegar, acetic acid bacteria and yeasts balsamic vinegar
Other vegetal fermented food: role of micorganism in soia products, olives, sauerkrauts, coffe and cacao
G. A. Farris, M. Gobbetti, E. Neviani, M. Vincenzini “MICROBIOLOGIA DEI PRODOTTI ALIMENTARI” (2012) Casa Editrice Ambrosiana (CAE).
Slides used during frontal lessons
The teaching will be carried out through frontal lessons using slides that represent teaching material made also available online in pdf format for students
Assessment methods and criteria
Specific lessons aimed to assessing the state of learning will be carried out at the end of each part of the course. Final examination will be carried out by a written examination with open questions. Each questions will be evaluated in arrange between 18 and 30. The final evaluation will be obtained from the average achieved. The average achieved will be the same or more than eighteen in order to pass the exam