Critical Analysis Essay on Ways of Estimation of Shelf Life

The potential shelf life determination has practical significance to the consumers. It is a principal feature of quality control. There are various ways that the shelf-life can be estimated. There are broadly categorized as direct methods and indirect methods (International Association of Milk & Protection., 2013). Direct methods usually take a longer time of estimation. However, it produces more accurate results. The products are stored under selected conditions than the expected shelf-life and examined at intervals to see when the spoilage begins. Indirect methods, commonly referred to as accelerated method, are done within a short period but are usually less accurate. The factors that determine the rate of deterioration such as temperate are modified, and the rate of deterioration thus increases. Adjustments must always be made once the product reaches the market.

In the direct method, the food is stored for a period that is longer than the shelf-life. Afterward observation, testing and recording of changes in the various aspects of the product takes place. Indirect methods such as predictive models and calculations are necessary for prediction of individual products like sauces and pickles. Technical expertise is required for correct applications and interpretation of the results. Knowledge of compositional factors such as pH and water activity that influences the thriving of the microorganisms. Determination of shelf life involves two major categories. These are quality characteristics selection that deteriorates quickly in time and the modeling of change using mathematical formulae. According to Bernardi, et al. (2013), measuring a characteristic standard index can be used to evaluate the shell life. The changes of quality index with time is often represented by a kinetic equation.

A practical example of accelerated shelf-life experiment.

Challenge studies can also be used to evaluate what can happen to a food product during processing and storage (Pao, et al. 1998). Appropriate microorganisms are inoculated into the food product in a laboratory investigation, and the changes are studied and recorded. This procedure is often costly and time-consuming but is still a major procedure in both safety studies and shelf life determination.

Referencing from Revista Brasileira de Ciencia Avicola (2004), pathogenic organisms are likely to be present in low amounts, and they could grow during the period when the product is still fit for consumption. Knowledge of how fast they will grow and to what extent they will grow is important for the determination of the shelf life. Challenges studies are done where several strains of microorganism are inoculated into the food product. At intervals, the micro-organisms are tested to determine the progression of the micro-organism inside the food product at ideal temperatures. A growth curve is therefore established by plotting the change on a graph. If a number of pathogen levels can reach an amount that is unsafe before the food shows signs of spoilage, then the expiry date will be essential.

The pathogen Listeria monocytogenes is often likely to be present in ready to eat food (Nyenje, et al., 2012). At ideal temperatures, they can grow from a count of 10 per gram to 100000 per gram. This shows that the use of ideal temperatures in shelf life studies is more often than not misleading. The safety of the food product is dependent upon reducing the levels of contamination. Examples of such food include already prepared salads and a cold-smoked fish. If the levels of L. monocytegene presents are little, then the risks of development are low.

Reference List

Bernardi, D. C., Marsico, E. T. & Freitas, M. Q. d., 2013. Quality Index Method (QIM) to assess the freshness and shelf life of food products. Brazilian Archives of Biology and Technology, 56(4), p. 64.

International Association of Milk, F. a. E. S. & Protection., I. A. f. F., 2013. Food adulteration and Inspection. Journal of food protection., 58(2), pp. 937-1440.

Nyenje, M. E. et al., 2012. Foodborne Pathogens Recovered from Ready-to-Eat Foods from Roadside Cafeterias and Retail Outlets in Alice, Eastern Cape Province, South Africa: Public Health Implications. PubMed Central (PMC), 9(8), pp. 2608-2619.

Pao, S., Brown, G. E. & Schneider, K. R., 1998. Journal of Food Science. Challenge Studies with Selected Pathogenic Bacteria, 63(2), pp. 359-362.

Revista Brasileira de Ciencia Avicola, 2004. Scielo. Microbiological quality of poultry meat: a review, 6(3).

Links used

1. https://www.researchgate.net/publication/260164782_Ways_of_measuring_shelf-life_and_spoilage2.https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&ved=0ahUKEwiq8a7Rv7fTAhWJA8AKHWRCDL0QFgg4MAE&url=http%3A%2F%2Fcdn.intechopen.com%2Fpdfs%2F35124%2FInTech-Principles_and_methodologies_for_the_determination_of_shelf_life_in_foods.pdf&usg=AFQjCNGw6c6USGS7EABgI7VU4gegtVW0jg&sig2=laOhwSYbbvwWNMGBNfPM2w3. http://link.springer.com/chapter/10.1007%2F978-1-4615-5975-7_19#page-14.https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=7&ved=0ahUKEwiq8a7Rv7fTAhWJA8AKHWRCDL0QFghaMAY&url=https%3A%2F%2Fmpi.govt.nz%2Fdocument-vault%2F12540&usg=AFQjCNFfT29ayOSQ0DLG9XfgmIY3v9_qtg&sig2=SyqS7XPKX-5ReMqAQDsOdg5.https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=6&ved=0ahUKEwiq8a7Rv7fTAhWJA8AKHWRCDL0QFghUMAU&url=http%3A%2F%2Fwww.foodauthority.nsw.gov.au%2F_Documents%2Fscienceandtechnical%2Fshelf_life_testing.pdf&usg=AFQjCNE9f87YSRH5R60RFGBVfoXaIQj2gQ&sig2=fWl-3r8IDVCTRvOfSJHCmw