【摘要】 本文运用聚丙烯酰胺凝胶垂直板状电泳技术和酶活性测定相结合的方法,初步探明了红茶萎凋、揉捻、发酵和干燥工序中多酚氧化酶(PPO)活性及同工酶谱的变化动态,以及酶试液制备方法对PPO活性及同工酶的影响,发现造成萎凋期间PPO活性变化两种研究结果的原因,在于酶制液的制备方法不同。同时,在鲜叶和萎凋叶中发现了第7条小分子PPO组分。本试验还证明了红茶中残余酶活性的存在,并探讨了残余酶在贮藏中可能发生的作用。文中还探讨了PPO各组分在红茶制造中作用的大小,从酶学角度论证了萎凋工序的重要性。更多还原

【Abstract】 The variation of isozymes and activities of polyphenol oxidase (PPO) in withering, rolling, fermentation and drying phase during black tea manufacturing, and the effect of the methods used to prepare enzyme solution on the PPO activities, were investegated by means of polyacrylamide gel electrophoresis and enzyme activities measuring. It is found that the reason for two different research results of the variation of PPO activities during withering is the different methods used to prepare enzyme solution. There is a very small molecule fraction of PPO7 which hasn’t been reported before. It is proved that there are remnant PPO activites in made black tea. In this paper,the relative role of each PPO fraction and the importance of withering phase in black tea manufacturing, and the effect of remnant PPO of black tea during storage, were discussed.更多还原