青稞蕨麻酵素发酵工艺优化及其品质评价

Optimization of the fermentation technology and quality evaluation of highland barley and Potentilla anserine Jiaosu

该研究以16株植物乳杆菌(Lactobacillus plantarum)为研究对象,对其酸、糖耐受性进行分析,选取一株耐受性能优良的发酵菌株,并以筛选菌株为发酵剂,青稞、蕨麻为主要原料制备青稞蕨麻酵素。以超氧化合物歧化酶(SOD)酶活性为响应值,采用单因素试验及响应面试验对其发酵工艺条件进行优化,并对其理化指标及抗氧化活性进行分析。结果表明,确定植物乳杆菌LL6-1为发酵剂,最佳发酵工艺参数为:蕨麻添加量9.6%、发酵时间4 d,发酵温度30℃,在此优化条件下,SOD酶活性为1112.07 U/mL,总酸、还原糖、氨基酸、总酚、类黄酮含量分别为3.93%、29.22 mg/mL、1.06μmol/mL、3.03 mmol/L、184.91 mg/L。此外,其1,1二苯基-2-三硝基苯肼(DPPH)自由基、O_(2)^(-)·和·OH清除能力以及铁离子还原/抗氧化能力(FRAP)分别为1710.18μg Trolox/mL、777.17 U/L、1701.31 U/mL和6.39μmol/mL,表明青稞蕨麻酵素具有抗氧化活性。电子舌检测结果显示酸味、苦味、甜味、涩味和鲜味是该酵素的味觉指标,酸味最为突出。

Using 16 strains of Lactobacillus plantarum as the research objects,their acid and sugar tolerance were analyzed to select a fermentation strain with good tolerance,and highland barley and Potentilla anserine Jiaosu were prepared using the screened strain as starter culture,highland barley and P.anserine as main raw materials.With the superoxide dismutase(SOD)activity as the response value,the fermentation conditions were optimized by single factor tests and response surface tests,and the physicochemical index and antioxidant activity were analyzed.The results showed that L.plantarum LL6-1 was determined as the starter,the optimal fermentation parameters were as follows:P.anserine addition 9.6%supplemental level,fermentation time 4 d,and temperature 30℃.Under the optimized conditions,the SOD activity was 1112.07 U/ml,and the contents of total acid,reducing sugar,amino acid,total phenol and flavonoid were 3.93%,29.22 mg/ml,1.06μmol/ml,3.03 mmol/L and 184.91 mg/L,respectively.In addition,the 1,1-diphenyl-2-picrylhydrazyl(DPPH),O_(2)^(-) and OH radicals scavenging capacity and Ferric ion reducing/antioxidant power(FRAP)were 1710.18μg Trolox/ml,777.17 U/L,1701.31 U/ml and 6.39μmol/ml,respectively,indicating the highland barley and P.anserine Jiaosu had antioxidant activity.The results of electronic tongue test showed that sour,bitter,sweet,astringent and umami were the taste indexes of the Jiaosu,and sour was the most prominent.