柿子酵素发酵工艺优化及品质评价

Optimization of Fermentation Process and Quality Evaluation for Persimmon Jiaosu

以磨盘柿为原料制作柿子酵素,借助单因素及正交试验,以功能品质和感官品质为评价指标,探究柿子酵素的最优发酵工艺,并对其理化性质、功能品质和风味品质进行评价。结果表明,柿子酵素的最佳发酵条件为白砂糖添加量10%,发酵剂接种量0.10%,发酵温度30℃,发酵时间6 d。此条件下制得的柿子酵素总酚含量为(247.33±4.15)mg没食子酸/kg,糖度为(8.93±0.65)°Bx,酸度为(8.57±0.38)g/L,有机酸分布结果显示其中乳酸、乙酸含量较高,这对柿子酵素产品的功能特性和感官品质有直接贡献。抗氧化性能研究结果显示柿子酵素的DPPH自由基清除率为(90.23±4.40)%,ABTS+自由基清除率达(94.72±2.81)%,CAT活力为(426.62±6.90)U/mL,羟基自由基清除率为(45.18±4.76)%,表明该工艺条件下生产的柿子酵素抗氧化性能优良。气相色谱-质谱-嗅闻风味评价结果显示,柿子酵素中含有己酸乙酯、辛酸乙酯、苯乙醇、苯乙酸乙酯等特征香味物质,赋予其独特的香气。

In order to enrich the product categories of persimmon and expand sales channels,Mopan persimmon was employed as raw material in this study to investigate the optimal fermentation process of persimmon enzymes(persimmon jiaosu).Single-factor experiments and orthogonal experiments were conducted with functional quality and sensory quality as evaluation indexes.The physical and chemical properties,functional quality and flavor quality of persimmon enzymes were also assessed.The results showed that the optimal fermentation conditions of persimmon enzyme were as follows:10% sugar,0.10% inoculation amount,fermentation temperature of 30℃,and a fermentation period of 6 days.Under these conditions,the total phenol content of persimmon jiaosu was(247.33±4.15)mg gallic acid/kg,sugar content was(8.93±0.65)°Bx,and acidity was(8.57±0.38)g/L.The result of organic acid distribution analysis showed high contents of lactic acid and acetic acid,which can directly contribute to the functional characteristics and sensory quality of persimmon jiaosu products.The result of antioxidant property assay showed that the free radical scavenging rate of 2,2-diphenyl-1-picrylhydrazyl(DPPH)was(90.23±4.40)%,the free radical scavenging rate of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)diammonium salt(ABTS)was(94.72±2.81)%,the activity of catalase(CAT)enzyme was(426.62±6.90)U/mL,and the hydroxyl free radical scavenging rate was(45.18±4.76)%,indicating excellent antioxidant properties of persimmon jiaosu produced under the fermentation conditions.The result of gas chromatography-mass spectrometry-olfactometry(GC-MS-O)flavor evaluation showed that persimmon jiaosu contained characteristic aroma compounds,such as ethyl hexanoate,ethyl octanoate,phenyl ethanol,ethyl phenylacetate,imparting a unique aroma to the products.This study provides a reference for high value utilization and intensive processing of persimmon.