Subject: PHYSICAL AND SENSORY ANALYSIS OF FOOD (A.A. 2023/2024)
Food Technologies (lesson)
The course provides students theoretical and practical knowledge regarding to methods used in the physical and sensory analysis and, at the same time, provide the basis for them correct using
in the study of the quality characteristics of beverages and food products achieving reliable and reproducible results. During the course, factors influencing sensory analysis, management and training of judges, organization, and performance of a sensory study, data collection and statistical processing methods, analysis texture and rheological properties, color analysis of beverages and foods will be addressed. The aim will be providing students with all the necessary tools for the characterization of foods both in the context of quality control, typicality, and identity of the products themselves.
The student should have knowledge related to food composition, and basic statistical approaches.
3 CFU (24 ore): Role of physical and sensory analysis in the quality control and food process. Characteristics, conditions, and standards of the sensory laboratory. Anatomical and physiological bases of sense organs. Perception of the sensory stimulus, definition, and evaluation of perception thresholds. Factors influencing sensory verdicts.
Selection, and training of panel members. Sensory attributes of foods. Sensory vocabulary development and sensory sheets. Control of tasting conditions related to test room, product, and panel. Sampling, and sequences of tasting samples (randomized sequences). Scale of measuring responses. Discriminating test, descriptive and affective methods. Rapid methods in the sensory studies. Guidelines for choice of sensory techniques. Case studies: discussion of scientific paper and applications of the sensory analysis in the food companies.
1 CFU (8 ore): 1 CFU (8 ore): The perception of color. Compounds responsible for the color of food. Light and interaction with food. Food color changing during processing and storage. Color spaces, and color differences evaluation. Tristimulus colorimetry and applications.
1 CFU (8 ore): Introduction to rheology, and to the food’s rheological properties. Stress, deformations, shear rate, and elasticity. Viscosity and viscoelasticity. Shear stress vs shear rate, viscosity vs shear rate, and force-time curves. Viscometer and rheometer. Food texture and evaluations of compression test, snapping-bending, shear test, puncture test, penetration test. Texture profile analysis and force-time curves. Interpretation of the structure profile. Case studies: Tools for the assessment of the mixture properties: rheological properties of fruits and doughs. Discussion of scientific paper.
1 CFU (8 ore): Laboratory work consists of evaluation of perception threshold, discriminant and descriptive tests, statistical analysis of the results obtained. Application of compression test, shear test, penetration test on foods and using of colorimeter.
CFU (8 hours). Laboratory activities consist of:
• 1 Lab. Act. (2 hours): evaluation of recognition ability of taste and olfactory stimuli. Evaluation of the taste threshold (super tasters, medium tasters, and non-tasters). Collection of results and data processing by collective discussion.
• 1 Lab. Act. (2 hours): sensory vocabulary elaboration; Performing sensory tests based on the application of main sensory methods with samples, data processing, and discussion of the results obtained. Preparation of an (individual) report.
• 1 Lab. Act. (2 hours): application of compression, penetration, cutting methods on food. Evaluation of the texture profile and discussion of the results
• 1 Lab. Act. (2 hours): Measurement of food color by colorimeter methods and use spectrophotometer.
The course consists of lectures (5 CFU, 40 hours) supplemented by laboratory activity (1 CFU, 8 hours), and focus group in order to involve, and interest the students towards the topic giving interactions opportunities among students, and between students/teacher. These will simplify the understanding of topics. In addition, the course will provide seminars, and educational visits at research centres with extensive experience in the physical and sensory analysis applied to food. The course consists of lessons in the presence of the teacher or distance lessons through Microsoft teams platform during pandemic time. Teaching language is Italian, and the attendance is not compulsory, but strongly advised.
Learning is verified by oral assessment (20 min). The student will have to prove knowledge of the explained topics during the course, the physical and sensory analysis methods used in the optimization, and innovation of product and in the study and conservation of food quality. The student must be able to plan a study of sensory and consumer tests and know all the issues related to the topic. To achieve the 30/30 with honours, the student must have acquired an excellent knowledge of the topics of course, discuss them with appropriate expository language, have to ability to use and connect knowledge. Evaluation indicators: ability to use knowledge 40%; - to connect knowledge 30%; - to discuss topics 20% - to deepen topics 10%. The exam takes place during the academic calendar. For each exam session students must register using the Esse3 platform. There are no intermediate evaluations.
Knowledge and understanding
Student will acquire:
1) knowledge of the physical and sensory methods for monitoring food quality. In addition, the student will learn how to perform a sensory study, and the organizational system supporting it;
2) knowledge of the rheological behaviour of food, and the chemical of the colour. These will allow the texture and color evaluation of food and correlation between sensory and instrumental analysis.
These knowledges will improve the comprehension skills of the student regarding the importance of learned procedures and methods in the food quality control and management.
Ability of apply knowledge and understanding
At the end of course student will skill:
1) in the selection of sensory and physical methods to control, management, and assurance of food quality;
2) in the planning, management, development, and optimization, if necessary, of sensory and instrumental studies for evaluation of sensory and physical proprietors. In addition, student will skill in the management of problems and provide solutions regarding applications of food sensory and physical methods.
Through the knowledge acquired, student will have a good level of:
1) autonomy in in the planning, implementation and management of a study regarding to the physical and sensorial characteristics of food;
2) a good making judgement on the effects of a process of transformation, preservation, packaging on the food sensory and physical properties, contributing to the improvement of food quality in relation to business problems or specific requirements.
Direct exchange of views between student and teacher during the course, case studies, and participation at seminars allow the student to acquire communication skills in order to solve problems, criticality in the context of the deal topics.
Ability to learning
At the end of course, students will acquire skills for becoming autonomous in finding informative material in order to catch up on the applications and studies in this field.
1) Valutazione sensoriale – Aspetti teorici, pratici e metodologici. E. Paglierini – Ed. Ulrico Hoepli; Milano;
2)Food Texture and Viscosity, Concept and Measurement, 2nd edition, Bourne, 2002, Academic Press, Food Science and Technology International Series.
3) Materiale didattico distribuito durante il corso (che sarà fornito durante le lezioni ad ogni fine di argomento trattato. Inoltre, il materiale di didattico è caricato anche sulla piattaforma di teams).
I libri di testo sono disponibili presso la BSI.
Testi consigliati per approfondimenti che lo studente potrà usare in modo facoltativo ad integrazione del materiale didattico e dei test consigliati:
1) Introduzione all’analisi sensoriale degli alimenti. C. Pompei e M. Lucisano –– Ed. Tecnos s.r.l.
2) Sensory evaluation techniques (1999). M. Meilgaard, G.V. Civille, B. T. Carr. – 3rd Ed. - Boca Raton: CRC, 1999.
3) Sensory evaluation of food: statistical methods and procedures (1986). M. O'Mahony. - New York; Basel: Dekker.
4) Sensory evaluation practices (2004). H. Stone and J. Sidel. - 3. Ed. – San Diego, CA; London: Elsevier Academic Press,.
5) Sensory evaluation of food: principles and practices (1999). H.T. Lawless, H. Heymann. - Berlin: Springer.
6) Physical Properties of Foods. Serpil Sahin and Servet Gulum Sumnu - Springer, New York, NY, USA, 2006.