The Changes During Dry-cured Ham Ripening And Their Potential Effects On Human Health

Dry-cured ham is mainly made of the fresh pork hind or front legs. It is a kind of cured meat product which is dry cured in low-temperature(0~4℃) and dried in high temperature(15~20℃) for ripening. Because of its unique and rich cured flavor, lots of consumers like it. Many studies have shown that, the subcutaneous fat of Xuanwei ham makes a significant contribution to its flavor, while the occurrence of lipid oxidation and degradation leads to the production of new substances during the processing, and these substances may have an impact on the body. So it’s necessary to study the influence of these changes on the health of those who eat dry-cured ham so as to provide some theoretical basis for nutrition and safety of dry-cured ham.In this study, we used the subcutaneous fat of Xuanwei ham to study the quality changes including physical and chemical indicators(moisture content, pH, chloride content and fat content), lipid oxidation(TBARS), nutrition indicators(fatty acid composition and content) and the flavor during its ripening periods(0,3,6,12 and 18 months). And we studied the influence of the changes on the antioxidant capacity and lipid metabolism in rats through the determination of the level of MDA GSH-PX, NO, NOS, SOD, CAT in serum, MDA, GSH-PX levels in muscle and TCH, TG, HDL-C content in serum. The results showed that:(1) During ripening periods, the moisture content of the subcutaneous fat reduced significantly(10.60%~2.20%), pH decreased(6.57%~5.82%), fat and sodium content increased significantly, and the content of characteristic flavor compounds increased. Meanwhile, the degree of oxidation in fat grew significantly, with the content of monounsaturated fatty acids and polyunsaturated fatty acids reducing and the gradual increasing of trans fatty acid content, which indicated that the safety and nutritional value of Xuanwei ham were reduced during the ripening process;(2) the content of MDA in serum increased significantly when the rat was fed on dry cured ham subcutaneous fat with different ripening periods, GSH-PX, NO, SOD, CAT decreased significantly, and the level of NOS did not change significantly, which indicated that the longer the fat of ham was fabricated, the higher of the oxidation in rats was;(3) compared with being fed on fresh meat, the content of TCH, TG and HDL-C in rats’ serum increased significantly by being fed on dry-cured ham with different ripening periods, but the difference between ham in different periods was not significant.These results showed that the long fabrication process of ham leaded to the reduction of ham unsaturated fatty acids, the increase of saturated fatty acids, as well as severe increase of oxidation level, so that the consumption nutrition and safety decreased.