Three Plants Phenolics Affect Chinese Sausage, Fat And Protein Oxidation

In order to estimate the relation between lipid oxidation and sausage quality, three batches of sausages were treated with different packages, storage temperature, illuminations and antioxidants. Lipid oxidation was measured by determination of acid value, peroxide value and TBARs. It was found that three batches of sausages were in different oxidation degrees. Fatty acid composition of phospholipid and free fatty acid changed significantly in the process of production and storage, and were correlated well with lipid oxidation.The determination of oxidative indicators, volatile flavor compounds and sensory estimate were carried out during process and storage to analyse the correlation between lipid oxidation and sausages quality. Lipid oxidation showed a significant effect on smell, taste and colour quality of chinese traditional sausages. Chinese traditional sausages which peroxide value below15meq/kg showed an excellent quality, while peroxide value exceed18meq/kg showed a serious oxidative rancidity. According to the determination of volatile flavor compounds, lipid oxidation enhanced the formation of aldehydes which correlated well with sausages flavor quality. Hexanal, octanal, nonanal,2-nonenal, showed a positive effect on flavor quality of chinese traditional sausages significantly, heptanal,2,4-nonadienal,2,4-decadienal,2-heptenal,5-methyl-hexanal impacted flavor quality of chinese traditional sausages negatively. In addition, the accumulation of butanoic acid ethylester, hexanoic acid ethylester were beneficial to development of flavor quality of chinese traditional sausages.The determination of protein oxidation were carried out during process and storage to analyse the correlation between lipid oxidation and protein oxidation. Results indicated that inhibition of lipid oxidation could reduce total protein carbonyls significantly. Total protein carbonyls content strongly correlated with primary and secondary products of lipid oxidation. Furthermore, loss of protein sulfydryl groups was enhanced by secondary product of lipid oxidation, especially volatile aldehydes, rather than primary products of lipid oxidation.The effect of rosemary phenolic (RP), apple phenolic (AP) and grape seed phenolic (GSP) on lipid and protein oxidation of Chinese-style sausages stored for120d was investigated, comparing to BHT and ursolic acid (RT). Results indicated that AP, GSP and RP were more effective on inhibiting lipid oxidation in Chinese-style sausages during ripening and storage for120d than influences of BHT and RT on lipid oxidation in sausages. The strong antioxidant activity exhibited by three phenolics from plant investigated was related with their inhibition ability on formation of metmyoglobin by chelating iron from myoglobin competitively. Moreover, three phenolics from plant exhibit stronger phospholipid protective capacity than RT and BHT at the end stage of storage. GSP and RP showed more effective than AP, RT and BHT on inhibiting protein oxidation in Chinese-style sausages, so ephenolics from plant may inhibit protein oxidation effectively by inhibiting formation of peroxides, the primary lipid oxidation products, rather than the secondary products of lipid oxidation.