Effect and analysis of MAP on volatile flavor compounds in sturgeon(Huso dauricused × sturger schrenckii) caviar

Volatile compounds in different MAP sturgeon caviars during 0 ℃ cold storage were analyzed by combining solid phase micro- extraction( SPME) with gas chromatography- mass spectrometry( GC- MS). The compounds responsible for the flavor of sturgeon caviars were mostly aldehydes,among which hexanal had the most contribution. Modified atmosphere packaging( MAP) obviously increased the relative contents of hexanal,which reached 13.70% as highest.A stronger fatty,grassy and fishy smell especial in the third month was detected in MAP sturgeon caviars,when they had abundant volatile compounds. MAP could inhibit the oxidation of polyunsaturated fatty acids and the degradation of amino acids,and the change of ketones and alcohols contents were decreased as well. In addition,the MAP4 group treating with lowest concentration of CO_2( 30% CO_2+ 70%N_2) possessed obvious differences,for example,alcohols and esters had different content comparing with other groups,which verified a more concentration of CO_2 was better in storage.The results showed that MAP could affect odors of sturgeon caviar and extending shelf life.