植物油微波輔助甲酯化方法建立及鑑定方法研究

Rapid microwave-assisted methylation and authentication of plant oil

杜婷婷(Ting-Ting Tu)

指導教授 ： 凌永健

國立清華大學/理學院/化學系/碩士(2012年)

摘要

台灣常見的食用油有大豆油、花生油、芝麻油、茶籽油等。不肖業者為降低成本，開始將低價油混入高價油中，嚴重損害了消費者的權益甚至健康。本研究期望能利用植物油中的脂肪酸組成，並輔以指紋圖譜技術建立一植物油鑑定系統，以保障消費者權益、打擊摻偽油品。為使前處理步驟符合環境友好的綠色化學趨勢，將微波輔助加熱技術成功應用於油樣的甲酯化反應中，利用GC-MS定性分析植物油之脂肪酸組成，建立30張樣品標準指紋圖譜以及11張油種標準指紋圖譜，並進行四種油種辨別分析系統的訓練與建立，分別為判別分析、相似度分析、群集分析以及本研究所創新之二維散佈圖分析。系統建立後，將大豆油以10%、25%、40%、50%等比例分別摻入苦茶油與黑芝麻油中作為摻偽樣品，對所建立的四個分析系統進行驗證及摻偽應用。其中以群集分析系統以及二維散佈圖分析系統有較好的辨別能力，並以二維散佈圖分析系統較具有摻偽鑑定能力，可進一步利用此系統推算摻偽比例，經線性迴歸分析後可得苦茶油摻偽樣品及黑芝麻油摻偽樣品之摻偽比例鑑定極限值 (LOA)分別為0.73%、1.94%。本研究成功合併此二種分析系統建立一植物油鑑定系統，並具有分析摻偽比例的潛力。

關鍵字

植物油 ； 微波輔助 ； 甲酯化 ； 摻偽

並列摘要

There are many kinds of plant oils, such as soybean oil, peanut oil, sesame oil and camellia oil, which are common oils in Taiwan. Unscrupulous businessmen adulterate high-price oils with low-price oil to seek high profit, and which greatly damage the rights, interests and even health of consumers. To protect consumers and defeat the adulteration of commercial oils, this study was going to establish an authenticating system of plant oils. In order to make oil pretreatment fits the rule of green chemistry, microwave–assisted methylation was successfully applied. GC-MS was used to analyze fatty acid in oils qualitatively and establish 30 sample standard fingerprints and 11 species standard fingerprints. Discrimination analysis, similarity analysis, cluster analysis and the innovated 2-D diagram analysis of this study were trained and established by the fingerprints. After setting up these four analysis systems, camellia oil and black sesame oil were adulterated with ratio of 10%、25%、40%、50% of soybean oil as adulterated oil samples that were used to do the validation and application of adulterations of four systems. It shows that both cluster analysis and 2-D diagram analysis have better results, and latter can further get adulterated ratio of samples. Limit of authentication (LOA) of adulterated camellia oil and black sesame oil is 0.73% and 1.94%. In this study, we successfully established an authenticating system of plant oils by combining two analysis systems, and which could be utilized for adulterating ratio evaluated.

參考文獻

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