Antiseptics are natural or synthetic chemical ingredients used to add food, drugs, pigments, biological specimens, etc., to delay the growth of microorganisms or chemical changes. Nitrite and sulfur dioxide are one of the commonly used preservatives. The preservatives include benzoic acid, sodium benzoate, sorbic acid, potassium sorbate, calcium propionate and the like.
The effect of preservatives on microorganisms can only be achieved if sufficient concentrations are in direct contact with the microorganisms. The preservative is first contacted with the outer membrane of the cell, adsorbed, and passed through the cell membrane for cytoplasm, and then it can exert its effects in various parts, hinder cell proliferation or kill it. Therefore, it is actually the effect of preservatives on the cell wall and cell membrane, and on the activity of enzymes that affect cell metabolism or on the genetic structure of cytoplasmic parts.
It is understood that there are three main preservative preservative principles. One is to interfere with the microbial enzyme system, destroy its normal metabolism, inhibit the activity of the enzyme; the second is to make the microbial protein coagulate and denature, interfere with its survival and reproduction; The permeability of the plasma membrane of the cell inhibits the elimination of enzymes and metabolites in the body, resulting in its inactivation.
Preservatives are strictly regulated. Preservatives should comply with relevant standards: First of all, it is reasonable to use harmless to the human body; at the same time, it does not affect the digestive flora, which can be degraded into normal components of food in the digestive tract; The use of pharmaceutical antibiotics; no harmful components are produced when the food is heat treated.