| Pork is one of the most important meat in our country. With the development of economy and improvement of people's life, cooled pork accounts for a larger and larger part in the production and sale of crude pork.Cooled pork is the fresh pork which is cooled down instantly after butchering and kept in 04℃ during following processing, transportation and saling. Cooled pork is more tender, fresh, delicious and nutrient compared with hot fresh pork and frozen pork.The spoilage is the main problem of pork which is caused by the microorganisms during butchering, processing, packaging and transportation. Methods to prolong the shelf life of cooled pork include controlling temperature, preservatives, special packaging and so on. This paper mainly studies preservatives.This paper studies the effect of cetylpyridinium chloride (CPC), sodium hypochlorite(NaClO) and acidified sodium chlorite(ASC) on cooled pork. Pork is immersed in the different solutions made of the three chemicals. After immersion, the treated pork was kept in a refrigerator with the temperature of 5℃. The microorganism number, TVB-N, pH and sensory evaluation of the pork were evaluated on the days of 0,3,5,7.Firstly, CPC, NaClO and ASC were used separately, and results showed that the most suitable concentration for CPC was 0.075%, for NaClO was lOOppm with pH5.5, for ASC was lOOOppm with pH2.4. Besides, when the H3PO4:ClO2- ratio became higher, the preservation effects would be better.Secondly, CPC was added into NaClO and ASC. It's discovered that CPC could help to improved the preservative effect of ASC, while had no effect on NaClO. The most obvious promotion effect of CPC is for 500ppm ASC.Finally, several preservatives, including 0.075%CPC, lOOppmNaClO (pH5.5), 1000ppmASC (pH2.4), 1000ppmASC+high ratio H3PO4 (pH2.4), 1000ppmASC +CPC (pH2.4) were compared together. The order of their preservation effects was: ASC+CPC and ASC+H3PO4 are better than ASC, while NaClO and CPC are of least effect. |
