产低温蛋白酶动性球菌的筛选及其在低盐鱼露发酵中的应用  

Screening of Low-temperature Protease-producing Planococcus and Its Application in Low-salt Fish Sauce Fermentation

作　　者：周晶 袁丽[1] 高瑞昌[1] ZHOU Jing;YUAN Li;GAO Ruichang(School of Food and Biological Engineering,Jiangsu University,Zhenjiang 212013,China)

机构地区：[1]江苏大学食品与生物工程学院,江苏镇江212013

出　　处：《食品科学》2021年第8期122-128,共7页Food Science

基　　金：“十三五”国家重点研发计划重点专项(2019YFD0901903);现代农业产业技术体系建设专项(CARS-46)。

摘　　要：探究4株从传统虾酱中筛选出的动性球菌对低盐鱼露品质的影响。采用水解透明圈的方法,从传统发酵虾酱中筛选并分离出4株在低温条件(15℃)下具有蛋白酶活性的菌株。通过酶活力的测定(40℃)进行复筛,其中编号为XJ11的菌株酶活力最高,为(10.07±0.11)U/mL。通过形态学观察和16S rRNA序列比对,鉴定4株菌均属于动性球菌(Planococcus),分别命名为P.maritimus XJ2、P.plakortidis XJ10、P.dechangensis XJ11和P.rifietoensis XJ12。4株动性球菌在低温、低盐、碱性的环境中生长良好。动性球菌所产的蛋白酶在40℃、pH 9.0时有最高酶活力,并具有一定的耐盐性。将4株动性球菌作为起始发酵剂(1∶1∶1∶1,3%)应用到低盐鱼露的发酵中,结果表明:添加发酵剂的低盐鱼露氨基酸态氮质量浓度((1.33±0.08)g/100 mL)极显著高于未添加发酵剂的鱼露((0.89±0.02)g/100 mL,P<0.01),并且主要的挥发性风味物质含量也高于对照组,例如醇类、酮类、酸类、酯类和吡嗪。因此,该发酵剂能够提高低盐鱼露的氨基酸态氮含量并有效改善风味。We investigated the effects of four strains of Planococcus with protease activity at low temperature(15℃)isolated from traditional fermented shrimp paste on the quality of low-salt fish sauce.The strains were screened for their enzymatic activity at 40℃.Among these,strain XJ11 showed the highest protease activity of(10.07±0.11)U/mL.Based on morphological observation and 16S rRNA sequence alignment,all four strains were identified as Planococcus and named P.maritimus XJ2,P.plakortidis XJ10,P.dechangensis XJ11 and P.rifietoensis XJ12,respectively.The strains grew well in a low-temperature,low-salt,and alkaline environment.The protease produced by Planococcus exhibited the highest enzymatic activity at 40℃at pH 9.0 and showed good salt tolerance.A 1:1:1:1 mixture of the four strains was inoculated at 3%as a starter culture in low-salt fish sauce fermentation.The results showed that the amino acid nitrogen content of low-salt fish sauce inoculated with the starter culture was(1.33±0.08)g/100 mL,which was significantly higher than that of the control prepared without the starter culture((0.89±0.02)g/100 mL)(P<0.01).The amounts of the key desirable volatiles such as alcohols,ketones,acids,esters and pyrazine were higher than in the control.In summary,the starter culture increased the amino acid nitrogen content of low-salt fish sauce and improved the flavor effectively.

关 键 词：鱼露 动性球菌 蛋白酶 发酵 低盐 低温 

分 类 号：TS254.9[轻工技术与工程—水产品加工及贮藏工程]