摘要
研究统计了不同煮熬时间、温度、煮熬次数和茶水比条件下5种砖茶中氟的释放规律及其同摄入量的关系。结果表明,砖茶的水浸出氟含量占全氟含量的70.94%～83.34%,平均77.06%;砖茶氟的浸出量随着茶水比的降低先增大后降低,当茶水比1:100时,浸出量、浸出率以及人体摄入量均最大,茶水比1:150以下时氟的摄入量将在安全量以下;煮熬次数与砖茶氟浸出量呈显著负线性相关(p<0.05),舍弃第一泡不饮可使氟的摄入减少48.33%;砖茶中的氟的浸出量随时间的延长增加较快,浸出量与煮熬时间呈显著的线性相关(p<0.05)。煮茶时间控制在5min以下,基本能保证氟摄入不超过4mg/d;砖茶中氟的浸出量在70～80℃的温度区间内达到最大,当温度超过60℃后茶汤中的氟将超过安全摄入量。因此建议饮砖茶时,尽量增大饮茶时的茶水比,使第一泡茶稍微浸泡一会后舍弃,尽量使用低于60℃的温开水煮熬,同时延长每一泡茶的冲泡次数,减少每天的更换次数将更有利于健康。
Infusing time,temperature,times and tea-water ratio were examined for their effects on the release of fluoride from five kinds of brick tea.Results showed that the fluoride contents in tea infusion were about 70.94%～83.34% of the total fluoride in brick tea,with an average value of 77.06%.With the increase of tea-water ratio,the extracted fluoride content increased firstly,and then decreased.The highest fluoride content in tea infusion,extraction rate of fluoride and its intake were obtained with the tea-water ratio of 1：100.Safe intake amounts of fluoride in the tea infusion were found when the tea-water ratio was below 1：150.Fluoride release was significantly negatively linear-correlated with the infusing times（p0.05）.48.33% of the total fluoride intake can be avoided without drinking the first tea soup.The release of fluoride was significantly positively linear-correlated with the infusion time（p0.05）.It was found that fluoride intake was lower than 4 mg/day when the infusing time was of 5 minutes.Fluoride infusion amount reached its maximum value within the infusing temperature range of 70 ℃～80 ℃ and higher infusing temperature（60 ℃） led to higher fluoride content in the tea infusion than the safe level.It was thus suggested that safe fluoride intake from tea infusion can be ensured by increase of tea-water ratio,discarding the first soup,using water below 60 ℃ and reducing infusion times.
出处
《现代食品科技》
EI
CAS
2010年第9期934-937,共4页
Modern Food Science and Technology
基金
国家质量监督检验检疫总局专项资助
关键词
砖茶
氟
氟释放
浸出量
摄入量
brick tea
fluoride
fluoride release
infusion amount
absorption amount
