Course code PārZ6015

Credit points 2

Analysis of Food Shelf Life

Total Hours in Course80

Number of hours for lectures8

Number of hours for seminars and practical classes24

Independent study hours48

Date of course confirmation16.02.2011

Responsible UnitDepartment of Food Technology

Course developers

author prof.

Tatjana Ķince

Dr. sc. ing.

author Pārtikas tehnoloģijas katedra

Jeļena Zagorska

Dr. sc. ing.

Prior knowledge

Ķīmi5006, Chemistry of Natural Compounds

PārZ6001, Application of Food Additives

Course abstract

The study course “The analysis of food shelf-life” introduce and give possibility to get knowledge about different kind of factors, which influence food spoilage processes; determination of expiry date of food; it calculation and prognoses. The main problems will be discussed in the course: the main ways of food spoilage; control of moisture content in food; the thermostability of food; the control of the physiology of colour and hardness; the methods of determination of food spoilage level (identification, innovations, the analyses of results).

Learning outcomes and their assessment

After the course student will have:
• knowledge – in-depth knowledge and understanding of the processes that take place in food during storage, determination of the shelf life of food and the possibilities of its extension (workshops, practical works, individual work, test)
• skills to determine food spoilage ways and factors (intrinsic and extrinsic); ways of food spoilage, varying with storage conditions, recipe, technology, working with modelling programmes develop shelf-life detection schedule for specific product (practical works, individual work)
• competences: using knowledge and skills to determine shelf-life of specific product, defining main parameters, which should be controlled, frequency and conditions of the experiment, if possible accelerated shelf-life detection method can be used, offering shelf-life prolonging possibilities (practical works, individual work)

Course Content(Calendar)

1. Analysis and critical evaluation of ES and Latvian legislation according shelf-life, quality, healthy claims of food, discussion about food labels, good and bad examples (Lecture – 1h, Workshop – 1h).
2. Safety criteria of food, necessity for determination and its importance. Allergens, its indication necessity and importance, discussion (Workshop – 2h).
3. Used by and best before, determination mechanisms, main differences and discussion (Workshop – 2h).
4. Main factors affecting food quality. Its identification, determination and reasonable control justification during discussion (Lecture – 1h, Workshop – 1h).
5. Moisture content, water activity, pH, oks-redox potential meaning and regulation possibilities for shelf-life prolonging, discussion about factors, which influence product quality during storage (Lecture – 1h, Practical work – 1h).
6. Temperature, relative moisture content, light exposure, packaging materials influence on food shelf-life and quality, discussion about factors influencing food quality during storage (Lecture – 1h, Workshop – 1h).
7. Food spoilage mechanisms, regularities, examples and discussion (Practical work – 2h).
8. Microbiological spoilage of food products. Microorganisms, yeast, mould, its importance in food spoilage process, discussion about specific food products (Practical work – 2h).
9. Mailard reaction. Main influencing factors and mechanisms. Changes in colour, aroma, taste, energetic value. Mailard reaction and food antioxidant activity. Mailard reactions influence on food microbiological spoilage (Practical work – 2h).
10. Oxidation of lipids. Self-oxidation. Factors influencing lipid oxidation. Methods used for lipid oxidation measuring. Control of lipid oxidation process and predicting. Enzymatic lipid oxidation. Enzymes, lipids and food spoilage. Dairy, meat and fish product lipolysis, discussion (Practical work – 2h).
11. Physical spoilage, characterisation, mechanisms, influence on food shelf-life (Practical work – 2h).
12. Prolonging possibilities of food shelf-life. Traditional and alternative technologies, antimicrobial preparations, food additives, packaging materials etc. Discussion about food shelf-life prolonging possibilities, its necessity, utility and importance (Lecture – 1h, Workshop – 1h).
13. Food shelf-life detection methods, including accelerated shelf-life detection. Main princes. Kinetic modelling (Lecture – 1h, Workshop – 1h).
14. Detection of food product shelf-life based on enterprise standards or/and regulations. Main factors, testing criteria, detection frequency, repeatability, description and justification of methods. Analysis of the results, comparison, discussion about results interpretation (Practical work – 2h).
15. Detection of shelf-life, safety providing, shelf-life of the product predicting. Predicting modelling and its application (Practical work – 2h).
16. Test. Presentation and defence of the individual work, discussion about problem situation and possible solutions (Workshops – 2h).

Requirements for awarding credit points

Credit with mark.
In order to get the accumulative credit, the student must:
• participate in practical works (100%), workshops (100%) and lectures (70%);
• successfully write (the assessment must be at least “almost mediocre”) test (includes both test and open questions);

• develop and publicly defend the individual work, determining the shelf life for a chosen food product.

Description of the organization and tasks of students’ independent work

The student prepares and defends the independent work in accordance with the requirements, which must be submitted in writing before the defence to the lecturer of the study course. The maximum volume of the summary of the results of the individual work will be 20 A4 format pages. The summary should include the following points:
1. Introduction.
2. Chosen food product preparation technology and recipe.
3. Chemical composition of the chosen food product.
4. Factors influencing the quality of the chosen food product (intrinsic and extrinsic).
5. Possible types of damage to the selected food product and their prevention options.
6. Analysis of the shelf life and storage conditions of similar (if any) foods on the market.
7. Test plan for the selected food product quality parameters testing (sensory evaluation, acidity, humidity, etc.) during storage under different conditions (temperature, humidity, gaseous environment, light, etc.).
8. Description of testing methods (standards and equipment).
9. Analysis of the results obtained during testing.
10. Possibilities to extend the shelf life of the selected food product.
11. Conclusions and proposals.

12. List of used literature.

Criteria for Evaluating Learning Outcomes

The accumulative credit consists of the evaluation of the test and independent work, calculating the arithmetic mean.
A student can obtain a successful grade for a test if at least 60% of the questions have been answered correctly. Independent work is evaluated in accordance with the evaluation requirements specified in the task.

Compulsory reading

1. Food packaging and shelf life [elektroniskais resurss]: a practical guide / ed. G. L. Robertson. Boca Raton: Taylor & Francis, 2009. 404 p. ISBN 9781420078459 (e-book: PDF).
2. How to Determine the Shelf-life and Date Marking of Food [elektroniskais resurss] Ministry of Primary Industries, New Zealand government, 2012, 28 p.
3. Validation of Product Shelf-life (Revision 2), published by: Food Safety Authority of Ireland Abbey Court [elektroniskais resurss], 2014, 45 p.
4. Food safety in the 21st century: public health perspective / ed. R. Kumar Gupta, P. Dudeja, A. Singh Minhas. London: Academic Press, 2017, 584 p. ISBN 9780128017739.

Further reading

1. Galoburda R., Rakčejeva T. Pārtikas apstrādes alternatīvie procesi. Latvijas Lauksaimniecības universitāte. Pārtikas tehnoloģijas fakultāte. Jelgava: LLU, 2008. 94 lpp. ISBN 9789984784861. 2. Principles of food chemistry. Ed. J. M. deMan, W. J. Hurst; J. W. Finlej. C.Y. Lee; 4th edition. Cham, Switzerland: Springer, 2017. 607 p. ISBN 9783319636054. 3. Food microstructure and its relationship with quality and stability. Ed. S. Devahastin. Duxford, United Kingdom: Woodhead Publishing, 2017. 283 p. ISBN 9780081007648. 4. Chemistry: the central science T. L. Brown ... [et al.]. 14th edition, student edition. New York: Pearson, 2018. 107 p. ISBN 9780134414232. 5. Стеле Р., Срок годности пищевых продуктов. Расчёт и испытание. Санкт-Петербург, ПРОФЕССИЯ, 2008. 480 с.

Periodicals and other sources


Mandatory course of academic master study program "Food Science” (Faculty of Food Technology) and professional master study program “Food Hygiene” (Faculty of Veterinary Medicine) for full time students