The role of tea polyphenols: 1, there are obvious antioxidant effect, tea polyphenols in the removal of free radicals, antioxidant, anti-aging effect is very obvious. 2, there is a certain reduction in the risk of cardiovascular disease, because tea polyphenols can reduce the blood in the blood of the total cholesterol, triglycerides, thereby reducing coronary heart disease, myocardial infarction and other cardiovascular diseases in the efficacy of the very obvious. 3, there are obvious antibacterial effects For the prevention of infectious diseases, tea polyphenols have a very obvious antibacterial effect if properly ingested.

Determination: According to the tea polyphenol oxidation, the characteristics of some reagents color, commonly used at home and abroad, potassium permanganate titration method (Iowenthal-Neubaur method) and colorimetric method. The former is the application of indigo red (indicator) in the presence of potassium permanganate on the oxidation of tea polyphenols, according to potassium permanganate oxidation of the consumption of tea polyphenol content, the operation is simple and easy to implement. However, the end point of the titration is difficult to grasp, easy to cause errors. The latter is based on the principle that iron tartrate can generate purple-red complex with tea polyphenols, and the intensity of color development is proportional to the content of tea polyphenols to calculate the content of tea polyphenols. The determination method is simple, fast and reproducible. It has been listed as a national standard (GB 8313-87). Similar to the principle of these two determination methods: cerium sulfate titration, complexation titration, potassium oxalate phthalate colorimetric method, phenol colorimetric method, Folin-Dennis colorimetric method, ultraviolet spectrophotometric method and so on.