Food preservative and processing method thereof

The invention relates to the technical field of production of food preservatives, in particular to a food preservative and a processing method thereof. The method comprises the following steps: step 1, putting shells of shrimps and crabs into a concentrated alkali solution, and separating out deacetylated chitin at high temperature; step 2, taking out invalid solution and impurities, and leaving deacetylated chitin; 3, drying the separated deacetylated chitin, and grinding the dried deacetylated chitin into powder; 4, other raw materials are mixed together to obtain a mixture; and step five, stirring and mixing the powdery deacetylated chitin and the mixture to obtain the food preservative. The food preservative consists of the following raw materials in parts by mass: 6-9 parts of chitin powder; 0.5 to 1 part of protamine; 3-5 parts of propolis; 1-2 parts of an emulsifier; 1-2 parts of an aromatic; 2-5 parts of tea polyphenol; 1-3 parts of essential oil; and 3-5 parts of deionized water. 本发明涉及食品防腐剂生产技术领域，更具体