茶叶和茉莉花中八氯二丙醚的残留动态及降解

研究八氯二丙醚(S421)在27种农药中的残留量及其在茉莉花和茶叶中的降解动态.结果表明:在喷施农药的部分茶叶中有检出S421;S421在茉莉花中的残留期较长,半衰期为3.78 d,而在茶叶中降解较快,半衰期为1.90 d;S421在绿茶加工过程中呈降解趋势,降解率达46.54%;用含有S421的茉莉花窨制扁针茶,窨花后S421残留量上升;烘干可促使S421降解,以140℃烘干0.5 h的烘箱烘干法与中火烘干4 min的微波烘干法降解效果较好.

Residue dynamics and degradation of S421 in jasmine flower and tea

2,3,3,3,2',3 ',4',4 '-octachlorodipropylether(S421) was studied on its content in 27 kinds of pesticides,and its residue and degradation dynamics in jasmine flower and tea.The result showed,S421 residue existed in some tea plants sprayed with pesticides,the period of residue of S421 in jasmine flower was longer,the half degradation period was 3.78 days,but as short as 1.90 days in tea plants,indicating that its degradation was quicker in tea.In the manufacturing process of green tea,the degradability was 46.54%.In the scenting process of Bianzhen,the residue amonnt increased after every scenting with polluted jasmine flower,then it decreased after drying.In comparison with the treatments of physic degradation method,better effects could be achieved by oven drying at 140 ℃ for 0.5 h,or microwave oven drying at mediate power level for 4 min.