Question

A biological method of food preservation is
A.Freezing
B.Drying
C.Fermentation
D.Adding salt

Answer 1

Hint: The main aim of food preservation is to prevent spoilage and improve the shelf life of the food. There are many physical, chemical, and even biological methods of preservation. Fermentation is the biological preservation process also known as biopreservation, used to preserve foods such as kimchi, dry-aged meats, and even seafood.

Complete step by step answer: Preservation of foods is an age-old process where multiple techniques were employed centuries ago to store food for winter when food is scarce. Today many food preservation techniques are being used to improve the shelf life of various commercially available food products.
Preservation can be done employing various methods, but biological food preservation techniques mostly involve fermentation products. Fermentation is the process of allowing bacteria to digest complex sugars and the resultant byproducts produced by the bacteria prevent the growth of other harmful pathogenic microorganisms.
One such organism would be the Lactobacillus bacteria. This is a probiotic bacteria, which is not pathogenic to humans. When culturing foods with this bacteria, it produces several byproducts, such as lactic acid, hydrogen peroxide, and other metabolites that effectively prevent the growth of other organisms.
The byproducts create unfavorable growth conditions such as low pH, increased salinity, or even antimicrobial compounds such as antibiotics which effectively prevent food spoilage, and pathogenic attack. Fermentation is also preferred as it improves the taste, texture, and even aroma of certain foods
Examples of food preserved through fermentation as curd, cheese, kimchi, dry-aged beef, canned fish, etc.

Note: Fermentation involves allowing specific nonpathogenic microorganisms to digest and preserve foods.
These organisms produce various byproducts that prevent the growth of other organisms and prevent spoilage.
Freezing and drying are physical methods of preservation whereas adding salt is a chemical method of preservation.
Organisms used for food fermentation are lactic acid bacteria species and yeast species.