为了探究不同菌种组合发酵对苹果酵素抗氧化功能的影响,研究了酿酒酵母+乳酸菌(鼠李糖乳杆菌或植物乳杆菌)组合发酵制备苹果酵素的工艺以及酵素的抗氧化功能.以陕西洛川富士苹果为主要原料,以超氧化物歧化酶(SOD)活力、总酸含量为评价指...为了探究不同菌种组合发酵对苹果酵素抗氧化功能的影响,研究了酿酒酵母+乳酸菌(鼠李糖乳杆菌或植物乳杆菌)组合发酵制备苹果酵素的工艺以及酵素的抗氧化功能.以陕西洛川富士苹果为主要原料,以超氧化物歧化酶(SOD)活力、总酸含量为评价指标,通过单因素和响应面试验优化了苹果酵素制备工艺,并对酵素的抗氧化功能进行了初步检测.苹果酵素最佳制备工艺关键参数为:苹果汁中添加5.5%w/v蔗糖并调节苹果汁pH至4.5,接种酿酒酵母进行发酵,发酵温度29℃,接种量1%v/v,发酵20 h后苹果汁发酵液SOD活力达到峰值(149.32±2.58 U/mL);而后调节发酵液pH至6.2,接种鼠李糖乳杆菌继续发酵,发酵温度37℃,接种量1%v/v,发酵时间23 h.制备的苹果酵素SOD活力为158.54±1.32 U/mL,酿酒酵母浓度为7.66±0.20 lg CFU/mL,鼠李糖乳杆菌浓度为6.47±0.14 lg CFU/mL,总酸含量为3.98±0.34 g/L.苹果酵素羟基自由基清除率、铁离子还原力以及总酚含量相比于对照组(未发酵苹果汁)分别提高了90.70%、77.78%和93.23%,表现出良好的抗氧化性.上述结果表明:酿酒酵母+鼠李糖乳杆菌组合发酵可显著改善苹果抗氧化功能特性.展开更多
Classroom observation is a means of doing research into what occurs in classrooms by systematically observing and keeping records of classroom events.Classroom observation plays very important role in teachers’evalua...Classroom observation is a means of doing research into what occurs in classrooms by systematically observing and keeping records of classroom events.Classroom observation plays very important role in teachers’evaluation and development.Summative and formative functions are the two main purposes that classroom observation serves.Three steps are involved in the classroom observation.Preparations are made before the observation.Various observational techniques or tools are used to collect data during the observation.Reflection and feedback are needed to improve classroom performance and competence.展开更多
文摘为了探究不同菌种组合发酵对苹果酵素抗氧化功能的影响,研究了酿酒酵母+乳酸菌(鼠李糖乳杆菌或植物乳杆菌)组合发酵制备苹果酵素的工艺以及酵素的抗氧化功能.以陕西洛川富士苹果为主要原料,以超氧化物歧化酶(SOD)活力、总酸含量为评价指标,通过单因素和响应面试验优化了苹果酵素制备工艺,并对酵素的抗氧化功能进行了初步检测.苹果酵素最佳制备工艺关键参数为:苹果汁中添加5.5%w/v蔗糖并调节苹果汁pH至4.5,接种酿酒酵母进行发酵,发酵温度29℃,接种量1%v/v,发酵20 h后苹果汁发酵液SOD活力达到峰值(149.32±2.58 U/mL);而后调节发酵液pH至6.2,接种鼠李糖乳杆菌继续发酵,发酵温度37℃,接种量1%v/v,发酵时间23 h.制备的苹果酵素SOD活力为158.54±1.32 U/mL,酿酒酵母浓度为7.66±0.20 lg CFU/mL,鼠李糖乳杆菌浓度为6.47±0.14 lg CFU/mL,总酸含量为3.98±0.34 g/L.苹果酵素羟基自由基清除率、铁离子还原力以及总酚含量相比于对照组(未发酵苹果汁)分别提高了90.70%、77.78%和93.23%,表现出良好的抗氧化性.上述结果表明:酿酒酵母+鼠李糖乳杆菌组合发酵可显著改善苹果抗氧化功能特性.
文摘Classroom observation is a means of doing research into what occurs in classrooms by systematically observing and keeping records of classroom events.Classroom observation plays very important role in teachers’evaluation and development.Summative and formative functions are the two main purposes that classroom observation serves.Three steps are involved in the classroom observation.Preparations are made before the observation.Various observational techniques or tools are used to collect data during the observation.Reflection and feedback are needed to improve classroom performance and competence.
