Any method by which food is protected against spoilage by oxidation, bacteria, molds, and microorganisms.
Traditional methods include dehydration , smoking, salting, controlled fermentation (including pickling), and candying; certain spices have also long been used as antiseptics and preservatives. Among the modern processes for food preservation are refrigeration (including freezing ), canning , pasteurization , irradiation, and the addition of chemical preservatives.