CHEMICAL, PHYSICAL AND SENSORY ANALYSIS OF FOOD

Academic Year 2022/2023 - Teacher: ELENA ARENA

Expected Learning Outcomes

1) knowledge and understanding: The aims of the course is to give to students the basics notions on the role of a laboratory of chemical, physical and sensoryal analysis of food. In particular, at the end of the course, the student will be able to choose the appropriate analytical and sensory evaluation methods, to prepare the sample, to carry out the analysis and to perform stoichiometry calculations and to understand the obtained results by comparing them with legal limits and /or quality parameters. 

2) ability to apply knowledge and understanding: the course, through the application of case studies in the laboratory, intends to provide the tools for the transfer of acquired knowledge for the choice of suitable analytical methods and the correct preparation of the sample.

3) autonomy of judgment: the course makes the student capable of analysis and critical evaluations concerning the choice of analytical methods and the interpretation of the experimental results obtained.

4) communication skills: the course will stimulate the student's ability to support and communicate the choices made regarding their skills

5) learning ability: at the end of the course the student is expected to have the ability to apply knowledge skills in different contexts, orienting study methods and reasoning towards a work perspective


Course Structure

The course includes 28 hours of lectures (or at a distance) and 42 hours of practical exercises, laboratory tests, carrying out exercises, laboratory reports.

The hours of frontal teaching will provide the student the knowledge of the basic notions of the used methods in the chemical, physical and sensory evaluation analysis of food products.

The hours of exercises will allow the student to be able to choose and apply the appropriate analytical and sensory evaluation methods.

If teaching is done in mixed or remote mode, specific changes to the program may need to be made.

Learning assessment may also be carried out on line, should the conditions require it.

Information for students with disabilities and/or DSA.
As a guarantee of equal opportunities and in compliance with current laws, interested students can ask for a personal interview in order to plan any compensatory and/or dispensatory measures, based on their specific needs and on teaching objectives of the discipline. It is also possible to ask the departmental contacts of CInAP (Center for Active and Participatory Inclusion - Services for Disabilities and/or DSAs), in the persons of professors Giovanna Tropea Garzia and Anna De Angelis.

Required Prerequisites

Basic knowledge of general, organic, analytical and food chemistry is essential to take the course.

Attendance of Lessons

Attending lectures is not compulsory but is strongly recommended for both the acquisition and application of knowledge.

Detailed Course Content

Laboratory safety, Concentrations (molarity, normality, weight / weight, weight / volume, volume / volume), dilutions, expression of results in the appropriate measure units; Gravimetric analysis, volumetric analysis. Validation of analytical methods: recovery, limit of detection and of quantification, accuracy and precision, RSD e (RSD) r. Systematic and random errors, calibration curve and linearity.

Analytical methods for the analysis of milk and dairy products; Analytical methods for the analysis of musts and wines; Analytical methods for the analysis of oils; Analytical methods for the analysis of honey; Analytical methods for the analysis of drinking water

Sensory analysis as a tool to define the quality of food; Physiology of the senses; The laboratory of sensory analysis; selection and training of judges; qualitative, quantitative, descriptive and affective discriminating tests.

Textbook Information

  1.  Cabras P., Tuberoso C.I.G. Analisi dei prodotti alimentari. Piccin Nuova Libraria S.p.a., 2013.
  2. Reg CEE 2568/1991; Reg CE 1989/2003; Reg CE 640/2008 english version
  3. Council Directive 2001/110/EC
  4. E. Pagliarini “Valutazione sensoriale aspetti teorici, pratici e metodologici” Ulrico Hoepli Editore SpA 2021 Milano. ISBN 9788820399801.
  5. Official Methods of Analysis of AOAC International 2005

Course Planning

 SubjectsText References
1Analyzes that measure physical properties: refractive index; Brix; density; specific gravity, freezing and boiling point1
2Gravimetric analyzes: principles and expression of results. Preparation of the sample Determination of moisture and dry residue ;. Determination of ashes. Determination of the fixed residue of water. 1
3Comparison of the methods for the extraction of the fatty substance. Determination of  fat in milk. Rose Gottlieb method1
4Volumetric analyzes: acid-base titrations. Analytical methods for the determination of acidity in food matrices and expression of the results;1 e 2
5Redox titrations: Fehling's assay: principle of the method and methodology1
6Determination of reducing sugars by the Fehling assay in different food matrices and expression of the results in the appropriate units of measurement1
7Protein determination: Kjeldhal's method, methodology and applications1
8The quality parameters of an oil and reference legislation: acidity; spectrophotometric analysis; gas chromatographic analysis of fatty acids; number of peroxides1 e 2
9Complexometric titrations: the determination of water hardness. Expression of results in the appropriate units of measurement1
10Quality parameters of honey; analytical methods and reference legislation1 e 3
11Quality parameters of milk; analytical methods and reference legislation1
12Determination of milk acidity and reference parameters. Development of formulas for calculating acidity and expression of the results in the appropriate units of measurement1
13The sensory analysis laboratory4
14Physiology of the senses4
15The judges and training4
16Discriminant methods4
17Descriptive methods4
18Affective methods4

Learning Assessment

Learning Assessment Procedures

The exam includes the practical test, the written test and the oral interview.

The practical test, for attending students, will take place at the end of the course in the didactic laboratory and will focus on the exercises conducted in the laboratory.

For non-attending students, the practical test will be replaced by a written test regarding the exercises carried out during the course.

The written exam will cover the solution of typical laboratory problems, application of stoichiometric calculations, calculation of analyte concentrations and interpretation of results (maximum duration 2 hours). Passing the written test allows access to the oral interview. The period of validity of the written test is limited to the date of the exam, therefore, if the student passes the written test but does not pass and / or does not show up and / or withdraws from the oral exam, the validity of the written test lapses.

Verification of learning also takes place through an oral interview. The oral interview will focus on:

- on the analytical methods that must be exposed indicating: the principle of the method, the procedures and any relevant legislation (see program).

- on sensory analysis (see program).

The elements of evaluation of the oral interview will be: learning ability and level of depth of the topics covered, properties of synthesis and presentation and reasoning skills of the student; relevance of the answers to the questions asked; the quality of the contents and the ownership of technical language; the ability to connect with other topics in the program.

The final grade out of thirty (exam grade) comes from the arithmetic average of the grades (out of thirty) obtained in the three tests (practical test grade + written test grade + oral interview grade / 3) and reflects the following scheme:

Unsuitable

Knowledge and understanding of the topic: Important shortcomings. Significant inaccuracies

Ability to analyze and synthesize: Irrelevant. Frequent generalizations. Inability to synthesize

Use of references: Completely inappropriate

18-20

Knowledge and understanding of the topic: At the threshold level. Obvious imperfections

Ability to analyze and synthesize: Just enough skills

Use of references: As appropriate

21-23

Knowledge and understanding of the topic: Routine knowledge Analysis and synthesis skills: It is capable of correct analysis and synthesis. Argue logically and consistently

Use of references: Use standard references

24-26

Knowledge and understanding of the topic: Good knowledge

Analysis and synthesis skills: Has good analysis and synthesis skills. The arguments are expressed consistently

Use of references: Use standard references

27-29

Knowledge and understanding of the topic: Knowledge more than good

Ability to analyze and synthesize: He has considerable abilities of analysis and synthesis

Use of references: Has explored the topics

30-30L

Knowledge and understanding of the topic: Excellent knowledge

Ability to analyze and synthesize: He has considerable abilities of analysis and synthesis.

Use of references: Important insights ..

Verification of learning can also be carried out electronically, should the conditions require it

Examples of frequently asked questions and / or exercises

Quality parameters of honey and the analytical methods for their determination

Methods for determining the alcohol content of a wine

Spectrophotometric analysis of oils: analytical method and interpretation of results

Milk acidity and expression of results

Calibration line

Gravimetric analysis and expression of the results

Sensory analysis laboratory

Panel selection and training

The descriptive methods