Food Microbiology

Credits: 
6
Year of erogation: 
2021/2022
Unit Coordinator: 
Disciplinary Sector: 
Agricultural Microbiology
Semester: 
First semester
Year of study: 
2
Language of instruction: 

Italian

Parent activity: 
Splittings: 

Learning outcomes of the course unit

The teaching of Food Microbiology aims to enable the student to autonomously draw conclusions about the effect of the presence and development of different microorganisms (pathogens, alterative and virtuous) in foods in accordance with what is defined in the specific objectives of the Degree course in Food Science and Technology and food microbiology area.
In particular, the student must be able to understand the different meaning between the concept of microbial contamination and the effect of microbial growth in a food that is both negative in terms of transmission of foodborne illnesses and in terms of alteration of the food, which is positive in terms of positive food transformation.
At the end of the course, the student must know how and why a food can be altered due to microorganisms and how and why the main diseases originating from microorganisms can manifest themselves through the consumption of food
The student must be able to manage the principles underlying physical, chemical and biological treatments or combinations thereof to control the development of microorganisms in food.
The student must be able to use the scientific language and the specific lexicon of food microbiology appropriately, demonstrating the ability to illustrate and transmit the acquired concepts.

Prerequisites

Knowledge of general microbiology

Course contents summary

The first lessons are about topics of general interest related to microbial food 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

Course contents

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
The program of the practical lessons consists in the application of direct (microscopy) and indirect (agar plate count) methods to verify the presence or absence of a specific microorganism and to estimate the number of specific microbial populations in food

Recommended readings

Giovanni Antonio Farris, Marco Gobbetti, Erasmo Neviani, Massimo Vincenzini “Microbiologia dei prodotti alimentari” (2012) Casa Editrice Ambrosiana ISBN: 978-88-08-18246
Lesson slides

Teaching methods

The teaching will be carried out through frontal lessons with the help of slides that will represent educational material, supplementing the recommended text, made available on Elly in pdf format for students.
The lessons also include the discussion of examples of the last real cases. For this reason, the slides, which are gradually updated for each topic, will be uploaded to Elly before any subject is discussed and not all together at the beginning of the course.
The course includes practical and theoretical experience on the principles and methods of analysis that underlie research and the direct and indirect counting of microorganisms in food.
The content of the exercises lessons will be an integral part of the final evaluation.

Assessment methods and criteria

At the end of the course the level of learning of the expected results will be verified for all the contents offered during the lessons, including the lessons of exercises. The learning verification of the FIRST MODULE will be carried out through a single partial test by means of a written exam. The written exam, to be carried out within 1 hour and 30 minutes, consists of three parts.
Each part is formulated in order to establish the evaluation on the degree of achievement of the course objectives
1. The first consists of 10 questions that verify the achievement of the minimum knowledge of the fundamental concepts of the course. For this reason, only if the answer to all the questions (to closed answers) is correct, the following parts will be evaluated
2. The second part consists of 21 questions to assess the level of knowledge acquired in all the topics covered. Each correct answer is worth 1,5 points. The achievement of the sufficiency threshold of this second part is binding for the correction of the third part. The sufficiency of 18/30 is achieved with at least 12 correct answers. The vote achieved will weigh 70% on the voting of the first module
3. The third part consists of an open-ended question where the student must demonstrate the ability to apply the acquired competence to a typical case. The answer is also evaluated based on how the student is able to express himself correctly, with the specific scientific language of food microbiology. The answer will be evaluated at 30th. The vote obtained in this part will weigh 30% on the vote of the first module.
The achievement of 18/30 in this first module of the integrated course is necessary in order to support the learning verification of the second module.
The rating obtained in each of the two modules will weigh 50% on the final mark of the integrated course