Investigation and analysis of fluorine content in fresh tea leaves
In order to explore the fluorine content of fresh tea leaves,the fresh tea leaves were collected with different leaf positions,growth periods,seasons and regions,dried them,soaked them in boiling water bath to extract fluoride,and determined fluoride ions by selective electrode method.Through the comparison and analysis of data,the fluorine content,changing rules and influencing factors of fresh tea leaves were explored.The results showed that the fluorine content of fresh leaves in different leaf positions changed linearly:bud<first leaf<second leaf<third leaf<fourth leaf.The fluorine content of fresh leaves with different leaf ages changes linearly:one leaf in one bud<two leaves in one bud<three leaves in one bud<four leaves in one bud<five leaves in one bud.The fluorine content of fresh leaves was lower than that of old leaves,and it showed an upward trend with the increase of leaf age.This study provided a reference for the development of tea industry.
fluorine contentfresh tea leavesfluoride controlfluorine ion selective electrodefood safety