Food preservation methods based on factors influencing reaction rates”

Introduction

Food preservation involves food processing practices meant to prevent the growth of microorganisms, so the food retains its quality and maintains its nutritional value. Food spoilage occurs due to physical, chemical, and microbiological reactions. Since time immemorial, man has applied conventional and primitive ways to combat the reactions such as drying, freezing, chilling, and pasteurization. However, with innovation and technology, there has been a rise in sophisticated methods of preservation that alter microorganism’s reaction rates and prolong the food’s shelf life. Individuals have adopted advanced technologies like irradiation, high-pressure technology, and hurdle technology to preserve food. The primary objective of food preservation is to increase its shelf life while retaining its nutritional value to the body.

Food spoilage is the change in the quality of food that renders t unfit and undesirable for human consumption; it can result from physical, chemical, or microbiological reactions. Microbiological food spoilage occurs due to the growth of microorganisms that produce enzymes that cause objectionable taste, odor, texture, and appearance. Chemical food spoilage occurs when different components in the food react with each other or with added components affecting the quality of the food (Amit et Al. 6). Physical food spoilage occurs when moist foods get too dehydrated or dried to acquire too much moisture (Amit et Al. 3). Effective food preservation methods slow down or prevent the reaction of agents that cause spoilage. The preservation techniques that function by influencing reaction rates include; use of chemicals, low temperature, drying, fermentation, and Pasteurization

Preservation by use of chemicals

Chemical preservatives can control microbial food spoilage by interfering with the mechanism of cell division, permeability, and enzyme activities. The preservatives are capable of inhibiting, retarding, or arresting the growth of microorganisms; hence the food maintains its color, odor, texture, and taste (Rawat, 55). Chemical preservatives are considered great in preventing food spoilage; however, some can be harmful. For example, when consumed, nitrates convert to nitrites that react with hemoglobin to form met-hemoglobin, leading to loss of consciousness or death, mainly in infants. Artificial food colorings are also associated with hyperactive behavior in infants and could cause intolerance among asthmatic people. Therefore, chemical preservatives should be used with precaution, especially among infants, pregnant women, and persons with conditions such as asthma.

Preservation using low temperatures 

The use of low temperatures to preserve food is based on the fact that metabolic reactions of microorganisms are catalyzed by enzymes that are dependent on temperature. An increase in temperature increases the rate at which the enzymes catalyze the organisms while lowering the temperature slows down the enzyme catalytic effect (Goswami et Al. 42). As the water in food crystallizes to ice, it hinders the growth of microorganisms, causing spoilage. Preserving food at low temperatures does not eliminate the microorganisms since once the temperatures increase, they begin to grow again. Preservation by low temperature is easy, quick and affordable, and does not affect the food’s taste, color, or nutritional value.

Drying 

Drying or dehydration involves removing water from food substances through evaporation. Since water is a requirement for microorganisms and enzymes to activate food spoilage, dehydrating slows down their reaction rate, making the food last longer. Most microorganisms survive underwater activity above 0.95; the lowered moisture content inhibits their activities but does not fully inhibit the growth (Amit et Al. 7). Drying has several advantages, such as lowering the volume of food substances hence facilitates its storage, packaging, and transportation. However, this method of food preservation could lead to loss of flavor and aroma in some food substances. Prolonged exposure to extreme temperatures can also lead to the loss of nutrients in foods such as vitamins and proteins.

Fermentation

Fermentation in food preservation entails converting carbohydrates to alcohols and carbon dioxide using yeast and bacteria under anaerobic conditions. The process is employed in the leavening of bread, pickling vegetables created with vinegar Shrivastava and Samuel 1446). Fermentation functions through the desirable bacteria inhibiting the growth of the undesirable ones and lowering the PH of the food to inhibit the growth of the bacteria, causing spoilage. Therefore, the process functions by encouraging the growth of the desired bacteria and interfering with the reaction rate of the harmful ones. To stop the fermentation process, one can apply other means of preservation such as heating, drying, or freezing. These preservation methods stop the fermentation by inhibiting the growth of the microorganisms. Fermentation is a healthy preservation method as it enhances the flavors and texture of some foods (Shrivastava and Samuel 1445). also, the desired bacteria break down the food making it easy to digest, reduces toxicity, and decreases the cooking time.

Pasteurization 

Pasteurization is a preservation technique where food is heated to destroy the microorganisms and enzymes that cause food spoilage. Pasteurization is an effective preservation method; however, its success is determined by the temperature-time combination (Amit et Al. 9). Vat pasteurization requires constant supervision to avoid overheating or burning. The method has some drawbacks since the high temperature can interfere with foods’ nutritional value by damaging some vitamins, minerals, and the desired bacteria.

Conclusion

Food spoilage occurs when the quality of food becomes compromised, hindering its edibility. The spoilage occurs due to insect infestation, activities of indigenous enzymes or microorganisms, temperature, air, time, light, or physical damage. To retain the inedible food conditions, one has to apply several preservative methods, which function by altering microorganisms’ growth and reaction rate in the food, giving it longer shelf life. The methods discussed in this article inhibit the reaction of harmful microorganisms making the food last longer in good condition.

Works Cited

Amit, Sadat Kamal, et al. “A review on mechanisms and commercial aspects of food        preservation and processing.” Journal of Agriculture & Food Security 6.1 (2017): 1-22.        DOI 10.1186/s40066-017-0130-8

Goswami, Meena, et al. “Effect of Low Temperature Preservation on Quality Characteristics of            Meat.” Journal of Animal Feed Science and Technology 7.1 (2019): 41-45.

DOI: http://dx.doi.org/10.21088/jafst.2321.1628.7119.7

Rawat, Seema. “Food Spoilage: Microorganisms and their prevention.” Asian Journal of Plant     Science and Research 5.4 (2015): 47-56.

http://www.pelagiaresearchlibrary.com/

Shrivastava, Sanjana and Jastin Samuel. “Fermentation as a sustainable method of food.” Journal            of Emerging Technologies and Innovative Research 6.1 (2019): 1445-1450.

https://www.jetir.org/papers/JETIRDY06230.pdf