从4种酒曲中分离筛选乳酸菌,并通过七叶苷平板显色法结合酶活测定筛选出3株高产β-葡萄糖苷酶的菌株。通过16SrDNA基因鉴定其种属,研究了3株菌粗酶液的最适温度、pH,并对酶进行定位。应用高产β-葡萄糖苷酶的乳酸菌发酵葡萄汁酸面团制作面包,通过固相微萃取气相色谱质谱联用技术(GC—MS)分析了面包香气成分,并进行了感官评定。结果表明:酒曲中一共筛得124株乳酸菌,其中产β-葡萄糖苷酶的乳酸菌有28株,产酶能力最高的3株乳酸菌经鉴定为哈尔滨乳杆菌(Lactobacillus harbinensis,M12和M24)和戊糖片球菌(Pediococcus pentosaceus,J28)。用M12发酵葡萄汁酸面团制作面包(RSB),RSB中一共检测出52种风味物质,较普通酵母面包(CYB)的风味物质种类增加了52.9%,而风味物质总峰面积也提高了65.5%。经过感官评定,RSB的整体接受度优于普通酵母面包(CYB)及含未发酵葡萄汁的酵母面包(RYB)。
Three high producing β-glueosidase lactic acid bacteria strains were isolated and screened from Qu by eseulin plate colored method combining enzyme activity lest, then identified by 16S rDNA. The screened bacteria with bighest enzyme aetivity was used in raisin sourdough fermentation and bread making. After that, the aroma of the bread was analyzed by GC- MS as well as sensory evaluation. The results showed that among the 125 isolaled laclie acid bacteria, there were 28 strains which produce β-glucosldae. Thress strains showed high enzyme producing ability, they were identified as Lactobacillus harbinensis ( M12 , M24) and Pediococcus pentosaceus (J28). M12, which appeared the highest activity was used in raisin sourdough fermentation and bread making. Compared with tin. corn mon yeast bread, the number and lhe peak area of the aroma corn pounds in raisin sourdough bread increased by 52.9% and 65.5%. Be sides, raisin sourdough bread is more acceplable than eommon yeast bread and raisin yeast bread in sensory ewdualion.