Biotechnology can convert nonedible and perishable food item to palatable and longer shelf life food, which is safe and improved quality in terms of nutrition and physicochemical and sensory properties. One-third of the processed foods of the world are fermented foods either natural or intentional fermentation adding microbial strain. Improper fermentation can cause production of toxin; therefore, quality control is most essential. Biotechnology can improve the edibility, consistency, and shelf life of food by preventing the growth of unwanted toxin-producing microorganisms naturally present in foods, production of antimicrobial agent to kill undesirable putrefactive microorganisms. Fermentation process raise the dietary value of the food along with the biosynthesis of vitamins, necessary amino acids, food flavoring, additives, preservatives, and proteins by improving the protein and fiber digestibility. Biotechnology has an essential function in protein engineering. Biotechnology also helps to identify pathogens and pesticides present in the food by ELISA and microarray.