Learning objectives
Module 2 of the course on Food Hygiene and Industrial Microbiology aims at understanding the effect of the presence and development of alterative and virtuous microorganisms in food. In particular, the knowledge concerning the main alterations originated by micro-organisms in food and to the changes made by micro-organisms in fermented foods must be developed. The intrinsic, extrinsic and implicit factors that influence the development and survival of microorganisms in food must also be known. Knowledge of these aspects will provide the essential elements for understanding the role of micro-organisms in food production and their impact on food quality. The use of this knowledge will also allow us to understand the principles of micro-organism control through physical, chemical and biological treatments or combinations thereof. The teaching aims to put the student in a position to draw conclusions about the effect of the presence and development of different microorganisms in food.
Prerequisites
no prerequisites are required. The topic of the introductory lectures will be the basic microbiology necessary to face the course.
Course unit content
The first lessons are about topics of general interest related to microbial contamination and the effect of their development in food, the role of different microorganisms in different food (food spoilage, food fermentation)
The second part of the course are about the methods that can be used to analyze the presence of microorganisms in 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
Full programme
The microbiological quality of foods.
The microorganisms in fermented and non fermented foods. Microorganisms in foods: bacteria, yeasts and moulds.
Microorganisms as indicators of process and contamination.
The contamination of foods.
Pro-technological microorganisms: fermentation.
Spoilage microorganisms: food degradation.
Factors which influence the growth of microorganisms in foods: temperature, pH, Aw, potential redox and availability of oxygen, food composition.
The control of growth and survival: checking pH.
Checking the Aw, use of low and high temperatures, packaging and protective atmospheres.
Other technological interventions that impact microorganisms: treatment with ionized radiation. Applications of high pressure and electric pulses.
Food additives addition.
Non fermented Foods.
Meat, fish, poultry, vegetables, fruit, milk and soft drinks
Fermented Foods. Cheese and fermented milk, fermented vegetables, wine, beer, bakery products, sausages
Bibliography
Giovanni Antonio Farris, Marco Gobbetti, Erasmo Neviani, Massimo Vincenzini “Microbiologia dei prodotti alimentari” (2012) Casa Editrice Ambrosiana ISBN: 978-88-08-18246
Teaching methods
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
Assessment methods and criteria
At the end of each part of the course during the course there are periodic lectures dedicated to classroom discussion with the students aimed at verifying the learning status.
The final learning check will be carried out through a single written exam (for the whole integrated course), 1,5 h long, organized in open questions (5). Each question will be evaluated in 30ths and the average of the votes in the applications will constitute the final grade. The threshold of sufficiency will be reached if the average achieved will be equal to or higher than eighteen thirty
Other information
Books for further information: Jay J.M., Loessner M.J., Golden D. A. “Microbiologia degli alimenti”. Springer (2009).
Galli Volonterio A. “Microbiologia degli alimenti”. Casa Editrice Ambrosiana (2005).
