Food microbiology is the study of the microorganisms that inhabit, create, or contaminate food which include the study of microorganisms causing food spoilage. Good bacteria like probiotics are becoming increasingly important in food science. In addition, microorganisms play a crucial role for the production of foods such as cheese, yogurt, bread, beer, wine and other fermented foods.
In food microbiology, food spoilage is defined as damage or injury to food rendering for human consumption. Food should be considered as spoiled if it is contaminated with pathogenic microorganisms or with various poisonous agents such as pesticides, heavy metals etc. The causes of food spoilage are Growth and activity of microorganisms, Vermin, Enzyme activity, Physical changes and Chemical reactions.
Factors affecting microbial growth in food are intrinsic factors which are inherent in food are Hydrogen ion concentration (pH), nutrient content of the food, moisture content, antimicrobial substances like coumarins, lysozyme, aldehydic and phenolic compounds, allicin and polyphenols and biological structure. Extrinsic factors are temperature, relative humidity and atmosphere.
Primary Sources of microorganisms in food are Soil and water, Plant and plant products, Intestinal tract of man and animals, Food handlers, Food utensils, Animal hides and skins and Air and dust.
Food spoilage are approximately 1/3rd of all food manufactured in the world is lost to spoilage. Food spoilage depends on the microbial content of foods (microbial load) and shelf life which are perishable foods, semi perishable foods and non-perishable foods.
Contamination of food can be minimized by good management processes, maintaining sanitary purposes, rapid movement of food through processing plant and well tested preservative procedures.