Effects of natural extracts on lipid oxidation, pathogen growth, and kinetics of heterocyclic amine formation in beef.

摘要

Natural antioxidant and antimicrobial compounds are preferably employed in meat and meat products because of their potential health benefits and safety. The increasing demand for naturally occurring preservatives has led to the exploitation of more effective and safe compounds by the meat industry. Natural extracts containing polyphenolic compounds have been shown to be antioxidants and to have antimicrobial activity. These natural extracts can also reduce the formation of HAs because phenolic compounds can inhibit free radical reactions. In this study, natural extracts were used to inhibit lipid oxidation, microbial contamination, and the formation of mutagens. Grape seed extract (ActiVin(TM)) and pine bark extract (PycnogenolRTM) significantly improved the oxidative stability of cooked beef. Antimicrobial susceptibility tests showed that these natural extracts had lethal effects against foodborne pathogens. In raw ground beef, the numbers of E. coli O157:H7, L. monocytogenes and S. Typhimurium declined by 1.08, 1.24, and 1.33 log CFU/g, respectively at 1% PycnogenolRTM after 9 days of refrigerated storage. In cooked ground beef, ActiVin(TM), PycnogenolRTM, and oleoresin rosemary (OR) at 1% levels effectively reduced the populations of E. coli O157:H7, L. monocytogenes, S. Typhimurium, and A. hydrophila compared to the control. The formation of HAs increased with increasing time and temperature. Natural extracts, ActiVin(TM), PycnogenolRTM, and OR, effectively decreased the formation of polar and non-polar HAs. Therefore, the results suggest that natural extracts could be used to reduce lipid oxidation and pathogen growth and provide valuable information to modulate and inhibit the formation of HAs in cooked meats.