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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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