苗族酸酢鱼发酵过程中微生物群落、氨基酸及水分动态变化规律

Dynamic Changes of Microbial Community,Amino Acid Composition and Moisture Distribution during the Fermentation of Miao Ethnic Suanzuo Fish

利用Illumina HiSeq测序及低场核磁技术,针对苗族酸酢鱼发酵过程中的品质变化规律进行研究。结果表明,乳酸杆菌属(Lactobacillus)、魏斯氏菌属(Weissella)和葡萄球菌属(Staphylococcus)是发酵中的优势菌属。发酵至第24天时,酸酢鱼发酵菌群中葡萄球菌属相对丰度最高,达到64.65%,其次为四联球菌属(Tetragenococcus)、乳杆菌属、巨球菌属(Macrococcus)和魏斯氏菌属。发酵成熟(第24天)的酸酢鱼中总游离氨基酸含量从380.61 mg/100 g增加到1 406.09 mg/100 g,呈味氨基酸有天冬氨酸(Asp)、谷氨酸(Glu)、丙氨酸(Ala)、缬氨酸(Val)、甲硫氨酸(Met)、苯丙氨酸(Phe)、赖氨酸(Lys)和组氨酸(His),Glu的味道强度值为30.69,对贵州酸酢鱼的整体滋味贡献最为显著。鱼肉中的不易流动水和自由水的含量显著下降,结合水相对含量逐渐上升,该变化与鱼肉质构变化规律一致。本实验为我国民族特色水产食品的工业化开发提供了一定理论支持。

In this work,the changes of the microbial community structure,taste and water distribution during the fermentation of Suanzuo fish were investigated.The microbial community was detected by Illumina MiSeq sequencing.Lactobacillus,Weissella and Staphylococcus were found to play the dominant role in the fermentation process.The abundance of Staphylococcus attained the maximum value of 64.65%on day 24,followed in decreasing order by Tetragenococcus,Lactobacillus,Macrococcus and Weissella.After completion of the fermentation on day 24,the concentration of total free amino acids increased to 1406.09 mg/100 g from 380.61 mg/100 g.The taste-active amino acids Asp,Glu,Ala,Val,Met,Phe,Lys and His were detected in Suanzuo fish.In the product,the taste activity value(TAV)of Glu was 30.69,which made Glu the most prominent contributor to the overall taste of Suanzuo fish.It was observed that the percentages of immobile and free water decreased obviously while the percentage of bound water increased gradually during the fermentation process.This change was consistent with the change of fish flesh texture.This study provides theoretical support for the industrial development of traditional ethnic aquatic foods in China.