冷藏和热加工对鲢肌肉主要滋味活性物质的影响

Effects of cold storage and heating on the taste active compounds in silver carp(Hypohthalmichthyx titrix) flesh

以鲢(Hypophthalmichthys molitrix)为原料,通过滋味活性值(taste active value,TAV)和味精当量(equivalent umami concentration,EUC)2种滋味表征方法,研究冷藏和热加工对鲢肌肉中滋味活性物质的影响。结果表明:鲢肌肉中主要滋味活性物质是谷氨酸(Glu)、组氨酸(His)、肌苷酸(IMP)、钾和钠。在5℃冷藏过程中,IMP含量迅速下降,次黄嘌呤(hypoxanthine,Hx)和Glu含量增加,His、K、Na含量基本不变。新鲜鲢肌肉在100℃加热30min后,IMP含量迅速降低,而其他滋味活性物质含量的变化相对较小。鲜味氨基酸和核苷酸及其降解产物的协同作用对加热后的鲢肌肉的鲜味贡献非常显著,EUC达到0.4g MSG/100g。冷藏不同时间后再加热,鲜味活性物质对鲢肌肉的鲜味贡献程度在冷藏3d内较缓慢下降,在第5天急剧下降。苦味活性物质对加热后的鲢肌肉的苦味贡献程度随冷藏时间延长逐渐上升。

Effects of cold storage and heating on the taste active compounds in the flesh of silver carp（Hypohthalmichthyx titrix）were studied by taste active value（TAV）and equivalent umami concentration（EUC）methods.Glutamic（Glu）,histidine（His）,inosine monophosphate（IMP）,potassium（K）and sodium（Na）were proved to be the major taste active compounds in the flesh.During cold storage at 5℃,IMP content decreased rapidly,hypoxanthine（Hx）and Glu increased,His,K and Na kept constant.IMP in the raw fish flesh decreased rapidly after heating at 100℃for 30 min,while changes of other taste active compounds were relatively small.Synergistic effect between flavor amino acid and nucleotide degradation products was significantly contributed to increasing umami of cooked fish flesh.EUC in the cooked fish flesh was 0.4g sodium glutamate/100 g.Raw fish flesh was stored for different time followed by cooking at 100℃for 30 min,degree of contribution by umami taste active compounds to cooked fish flesh decreased slowly within 3days＇ storage,while it decreased rapidly on the 5th day.Degree of contribution by bitter taste active compounds increased with storage time.