摘 要:建立一種用于食醋中可能殘留的甲醇和乙醇的頂空氣相色譜檢測方法,并討論了各種條件對測定的影響。方法采用氫火焰檢測器檢測,甲醇和乙醇能夠完全分離,線性良好,方法檢測限分別為8.91mg/L和7.28mg/L,6次測定的相對標準偏差分別為5.31%和3.01%,樣品的加標回收率分別為96.9%~94.2%。測定了6種樣品中的甲醇和乙醇含量,方法簡便、快速、重現性好,基本上能滿足食醋中甲醇和乙醇含量的分析。
關鍵詞:頂空氣相色譜甲醇乙醇
中圖分類號:TS264.21文獻標識碼:A文章編號:1674-098X(2011)05(b)-0120-02
Determination of Methanol and Alcohol Content Used for Vinegar by Head-space Gas Chromatography
Kong Xiang-wei ,Tang Ming-he
Zhejiang University of Technology,Hangzhou 310000,China
Cangnan County Institute for Technical Supervision and Testing of Quality,Wenzhou 325800, China
Abstract:An analytical method was developed for the determination of methanol and alcohol used for Vinegar by head-space gas chromatography,and various conditions effect on the results were discussed.Hydrogen flame ionization detector was selected,and methanol and alcohol were separated from each other completely.Results showed the good linearity range of this method.The detection limits of methanol and alcohol were 8.91mg/L and 7.28mg/L,the recovery ofmethanol and alcohol were 96.9% and 94.2% with precision of 5.31% and 3.01% RSD (n=6).During the experiments,6 kinds ofsamples were analyzed.This method is simple,rapid, accurate,and can be applied for determining the methanol and alcohol content used for vinegar.
Key words:head-space;gas chromatography;methanol;alcohol
食醋是我國勞動人民在長期的生產實踐中制造出來的一種酸性調味品。它能增進食欲,幫助消化,在人們飲食生活中不可缺少[1]。在我國的中醫(yī)藥學中醋也有一定的用途。全國各地生產的食醋品種較多。著名的山西陳醋、鎮(zhèn)江香醋、四川麩醋、東北白醋、江浙玫瑰米醋、福建紅曲醋等是食醋的代表品種。
食醋是用糧食等淀粉質為原料,經微生物制曲、糖化、酒精發(fā)酵、醋酸發(fā)酵等階段釀制而成。其主要成分除醋酸(3%~5%)外,還含有各種氨基酸、有機酸、糖類、維生素、醇和酯等營養(yǎng)成分及風味成分,具有獨特的色、香、味。它不僅是調味佳品,長期食用對身體健康也十分有益[2]。
對食醋中的揮發(fā)性有機物進行研究,不僅能鑒定食醋的品質,而且能了解其中的有害物質。目前我國對食醋中揮發(fā)性有機物的研究較少[3-4],特別是采用頂空氣相色譜法同時測定食醋中甲醇和乙醇含量。本文就是通過建立一種快速檢測方法,同時測定食醋中甲醇和乙醇含量。……