Learning outcomes of the course unit
The course of Food Microbiology aims to know the effect of the presence and development of pathogenic, spoilage and virtuous microorganisms in food. In particular, it should be developed knowledge about the major diseases originating from microorganisms through the consumption of food and alterations of microbial origin of food. Students must know the intrinsic, extrinsic and implicit factors that influence the development and survival of microorganisms in food. The knowledge of these aspects will provide the essential elements for understanding the role of microorganisms in food production, in particular in fermented foods, and their impact on food quality. The use of this knowledge will also allow to understand the principles of the control of microorganisms using physical, chemical and biological or their combinations. The course aims to put the student in a position to draw conclusions about the effect of the presence and development of different microorganisms in food as defined in agreement with the specific objectives of the Master of Science in Food Science and Technology and in agreement with the area of food microbiology.
The student should be able to appropriately utilize the scientific language and the specific lexicon of food microbiology, showing the ability to describe and transfer in oral and written form the acquired concepts.
Knowledge of general micorbiology
Course contents summary
The course I divided in two modules. The first module is divided in three part. The first lessons are about topics of general interest related to microbial contamination. The second part of the course are about the effect of the development of pathogenic, alterative and virtuous microorganisms in different foods. The third part of the course focuses on the factors that influence the growth of microorganisms in foods and the modalities of their control in order to prevent or reduce the development of pathogenic and spoilage microorganisms and promote the growth of microorganisms virtuous
The second module is dived in three part. The first lessons are about general aspect relating to spontaneous or driven 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 and their use as natural or selected starter The third part of the course deals with the characteristics and microbial dynamics responsible for the production of the main fermented foods of animal and vegetable origin
1 Module. Microbiology and foods: basic concept of microbial contamination and microbial development in food. Food microbial quality: Microorganisms as indicators of process and contamination. Microbial contamination and food. Microbial growth phases and factors conditioning their development in foods: i) intrinsic (water activity, pH, Red-ox, nutrient, antimicrobial compounds), ii) extrinsic (temperature, humidity, atmosphere packaging, preservatives, treatments) and implicit (microbial interaction). Spoilage of microbial origin: spoilage microorganisms and different type of food spoilage. Food borne microorganisms. Microbial food safety risk assessment of most important foodborne pathogens. Control of microorganisms in food. Safety, sterility and stability. Effect of some food control strategies: thermal treatment, water activity reduction, pH decrease, others. Main microbial aspects of: water and non alcoholic beverage, milk, meat, fish, fruit and vegetable, eggs, honey, preserved food
2 Module. Fermentation as a method of food processing. Spontaneous and driven fermentation. Presence of microorganisms in fermented food: Lactic acid bacteria, yeast, natural and selected starter. Microorganisms in dairy products: fermented milk, yogurt and cheeses. The microbiological role in wine production. Yeast, lactic acid bacteria and mould in red win, white wine and special wine. Role of microorganism involved in vinegar and balsamic vinegar production. Microbiological role in bear production. Microbiological role in meat fermentation. The microbiological role in bread production, yeast and lactic acid bacteria. Other vegetal fermented food: role of microorganisms in soia products, olives, sauerkrauts. Extractive fermentation: cacao
Giovanni Antonio Farris, Marco Gobbetti, Erasmo Neviani, Massimo Vincenzini “Microbiologia dei prodotti alimentari” (2012) Casa Editrice Ambrosiana ISBN: 978-88-08-18246-
slides of 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. The course will also be joined by lessons about methods of laboratory analysis regarding the protocol most commonly used for counting of microorganisms. The laboratory experience, individually carried out by each student, will be evaluated at the end of each day. Laboratory evaluation will be considered as a part of the final evaluation
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 program. Final examination will be carried out by two written examination with open questions. 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.
Lessons frequency for the first and the second module, is not mandatory, although strongly encouraged. Lab experiments are mandatory: the student will be admitted to the final examination only if he/she has attended all the lab experiments, eventually without one or more justified absence