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Abstract The objective of the study was to investigate the changing effects of chicken meat components(creatinine, reducing sugars and free amino acids)in quantities and the characteristics of Maillard reaction products (MRPs)on the IQ type mutagen formation under various storage conditions (25℃, ~24 hours;4℃, ~7 days;-18, -30, -40℃, ~12 weeks) during refluxing at 100~105℃ for 12 hours. The pH values of chicken meat stored at 25 and 4℃decreased at first and increased afterwards as time went on;while those of which frozen at -18, -30 and -40℃ still maintained at 5.79~5.92. The volatile basic nitrogen(VBN) of chicken meat stored at 25 and 4℃ increased as time went on and the increasing trend of which stored at 25℃ was higher than that of stored at 4℃; while those of which frozen at -18, -30 and -40℃ for 12 hours still maintained in the range of 5.49~12.04 mg/ 100g. The chicken meat juice after refluxing showed no mutagenicity. But the mutagenicity of the basic layer extract stored at 25℃ after 8 hours lowered obviously, while those which stored at 4, -18℃ increased after 3 days and 5 weeks respectively, and the increasing trend of which stored at 4℃ was more obvious than that of stored at -18℃. No obvious changes of mutagenicity of chicken meats frozen at -30 and -40℃ for 12 weeks were found. Obvious correlation between the consumed amounts of creatinine of chicken meats stored at 25, 4 and -18℃ and the mutagenicity of their basic layer extracts were observed (25℃, r=0.97; 4℃, r=0.99;-18℃, r=0.92, p<0.01), but not at -30 and -40℃; obvious correlation between the consumed amounts of reducing sugars of chicken meats stored at 25, 4 and -18℃ and the mutagenicity of their basic layer extracts were observed(25 ℃, r=0.96;4℃, r=0.96;-18℃, r=0.92, p<0.01), but not at -30 and The basic layer extract of chicken meat juice contained IQ-type mutagen including MeIQx, 4,8-DiMeIQx and PhIP. The tendency of the contents were PhIP>MeIQx>4,8-DiMeIQx, while those of mutagenic activities were MeIQx>4,8-DiMeIQx> PhIP. The changing trend of IQ-type mutagen amounts coincided with that of mutagenicity of basic layer extracts of chicken meat juice and the tendency was 4℃>-18℃>-30≒-40℃>25℃. Acid layer extract, i. e. Maillard reaction products (MRPs) of chicken meat juice showed no toxicity as well as mutagenicity, and inhibited the mutagenicity of indirect mutagen-IQ in a dose dependent manner in the order of 4℃>-18℃>-30≒-40℃>25℃. Besides, MRPs also possessed antioxidative activity, reducing power, chelating ability of copper and iron ions and scavenging ability of DPPH and hydroxyl radicals. MRPs in chicken meat juice contained thiophenes, pyrazines, furans and thiazoles. The tend
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