摘要
【目的】挖掘腐乳中高产蛋白酶且增咸能力强的微生物。【方法】通过干酪素平板和蛋白酶活力测定从不同发酵阶段的某腐乳样品中分离筛选菌株,并对其进行溶血性、药物敏感性等安全评价试验。结合感官评价和电子舌技术以及菌株发酵豆腐的提取液中可溶性蛋白和蛋白酶水解物的含量差异分析,筛选得到增咸和蛋白酶水解能力最强的菌株。最后对菌株进行分子生物学鉴定。【结果】共筛选出6株产蛋白酶能力强且较安全的菌株,其中菌株AF15-5电子舌的咸味响应值为17.76,明显高于空白组-0.91。其可溶性肽和氨基酸态氮含量也高于其他菌株,分别为3.48 g/100 g和0.67 g/100 g。鉴定结果显示,AF15-5为嗜麦芽寡养单胞菌(Stenotrophomonas maltophilia)。【结论】筛选出的菌株具有较强的产蛋白酶能力、蛋白质水解能力及安全性,应用于豆腐中具有良好的咸味呈现,可为后续“减盐”产品的开发提供可靠的微生物资源。
[Objective]To screen the strains from sufu with strongest protease production and saltiness-enhancing capability.[Methods]Strains were isolated and screened from sufu at different fermentation stages by casein plates and protease activity assays,then tested by safety evaluations such as hemolytic activity and drug sensitivity.Combined sensory evaluation,electronic tongue technology,and analysis of soluble protein and protein hydrolysate content in the extracts of fermented tofu,the strain with the strongest saltiness-enhancing and proteolytic ability could be selected.Finally,the strain was subjected to molecular biological identification.[Results]6 strains with stronger protease-producing capability and relatively higher safety were identified.Among them,strain AF15-5 exhibited a salty taste response value of 17.76 on the electronic tongue technology,significantly higher than the blank group(-0.91).Its soluble peptide and amino acid nitrogen content were the highest than other strains,at 3.48 g/100 g and 0.67 g/100 g respectively.Identification confirmed that AF15-5 belongs to the species Stenotrophomonas maltophilia.[Conclusion]The screened strain demonstrates stronger protease production,protein hydrolysis capability and safety,resulting in an obvious salty taste when applied to tofu,and provides reliable microbial resource for the development of“salt-reduced”products.
作者
张颖
邹谋勇
周红丽
ZHANG Ying;ZOU Mouyong;ZHOU Hongli(College of Food Science and Technology,Hunan Agricultural University,Changsha 410128,China;Dragon Brand Food Co.,Ltd.,Xiangtan 411100,China)
出处
《北京农学院学报》
2025年第2期72-78,共7页
Journal of Beijing University of Agriculture
基金
湖南省重点领域研发计划项目(2023NK2036)。
关键词
蛋白酶
菌株
筛选
腐乳
呈味
嗜麦芽寡养单胞菌
protease
strain
screening
sufu
taste study
Stenotrophomonas maltophilia
