29590 - Diagnostic And Predictive Microbiology

Learning outcomes

To give an overview of the potential application of matematical model and statistical procedures to the forecast of microbial growth in food products. To define the condition for the application of the most important mathematical models used in food industry

Course contents

Definitions, aims and development of predictive microbiology. Possible applications

Matematical models and microbial kinetics: empirical and mechanicistical models

Strategies for the acquisition of data: traditional techniques and innovative methods.

Primary models: growth microbial curves over time. Gompertz equation, Baranyi model, logistic equation. Death microbial curves: from the linear Bigelow model ti the description of non linear kinetics (loglinear models, Weibull equation and rate models for changing temperature).

Secundary models:Ratkowski equation. Experimental designs for the evaluation of the combined effects of different variables on microbial growth parameters and microbial metabolims. Polynomial equations

Tertiary models: applicative softwares for predictive microbiology and databases:: Pathogen Modelling Program, COMbase

Probabilistic models: from chi-squared to loglinear models. Logit equation.

Future perspective:supervisedand unsupervised methods

Application of predictive microbiology in food research and industry. 1. Evaluation of the effects of antimicrobials: the case of aroma compounds. Influence on the growth performance of microorganisms and on their death kinetics when associated with a thermal treatment. Advantages and critical points. 2. Study of the factors affecting biogenic amine production in foods. The case of fermented products. Experimental designs used to exploid decarboxylase activity in vitro and in vivo. 3. Spoilage of acid food. Traditional and innovative strategies to stabilize fruit based product. Evaluation of shelf life.

Readings/Bibliography

Specialistic monographies on the subject

Manuale di Microbiologia Predittiva (a cura di F. Gardini ed E. Parente). Springer Italia 2013

Teaching methods

Lectures

Specialistic seminars

Practical training lessons

Assessment methods

The evaluation of the preparation of the student will be assessed with an oral examination. Three questions will be requested to the student. The first will regard theorical aspects of microbial modelization, with particular emphasis on the principal equations presented during the courses. The second will be inherent to the possibility to apply the tools of predictive microbiology to practical aspects of food industry in order to evaluate the potential of the student to transfer theoretical concepts to real situations. The third will consist in a simple numeric exercise to evaluate the ability of the student to obtain information from the models in the predictive phase.For each of the first two questions a maximum of 12 points will be assigned, while for the third question a maximum of 9 points will be assigned.
The examination will be considered positive if at least 18 punti will be assigned to the student. Scores higher than 31 will result in the "laude".
The course of Advanced and Predictive Microbiology will be considere positive if the score of at least 18 points will be reached in both the units and the final scores will derive from the arthmetic means of the scores obtained in the two units.

Teaching tools

File di pptx (Slides)

Office hours

See the website of Fausto Gardini

See the website of Lorenzo Siroli