气相色谱-内标法测定白酒中3种高级脂肪酸乙酯含量

以乙酸正戊酯为内标物，建立了白酒中棕榈酸乙酯、油酸乙酯和亚油酸乙酯的气相色谱-内标法检测方法，并对市售不同香型白酒、不同品牌酱香型白酒中3种高级脂肪酸乙酯的含量分布规律进行探究。结果表明，3种高级脂肪酸乙酯的分离效果良好，线性范围为0.300 0～0.400 0 mg/mL，相关系数（R2）均＞0.999，精密度试验结果相对标准偏差（RSD）＜5%，加标回收率为94.01%～116.97%，检出限为0.003 2～0.003 5 mg/mL，定量限为0.010 9～0.011 7 mg/mL。11种不同香型白酒样品的3种高级脂肪酸乙酯含量在0～0.062 2 mg/mL之间，其中，酱香型白酒含量最高（0.062 2 mg/mL）；35种不同品牌酱香型白酒中3种高级脂肪酸乙酯总含量在0.003 5～0.075 8 mg/mL之间。该方法准确、灵敏度高，能对白酒中3种高级脂肪酸乙酯进行有效的分析，可用于酒类企业日常白酒分析检测。

Determination of 3 higher fatty acid ethyl esters content in Baijiu by gas chromatography-internal standard method

Using n-amyl acetate as internal standard, a method for the determination of ethyl palmitate, ethyl oleate and ethyl linoleate in Baijiu by gas chromatography-internal standard method was established. The content distribution of 3 kinds of higher fatty acid ethyl esters in Baijiu of different flavor types and sauce-flavor (Jiangxiangxing) Baijiu of different brands was also studied. The results showed that the separation effect of the 3 higher fatty acid ethyl esters was good, the linear range was 0.300 0-0.400 0 mg/ml, the correlation coefficient (R2) was all greater than 0.999, the relative standard deviation (RSD) of precision test results was less than 5%, the spiked recovery was 94.01%-116.97%, the detection limit was 0.003 2-0.003 5 mg/ml, and the quantitative limit was 0.010 9-0.011 7 mg/ml. The contents of 3 higher fatty acid ethyl esters in 11 different flavor type Baijiu samples ranged from 0 to 0.062 2 mg/ml, among them, sauce-flavor Baijiu had the highest content (0.062 2 mg/ml). The total contents of 3 higher fatty acid ethyl esters in 35 different brands of sauce-flavor Baijiu were 0.003 5-0.075 8 mg/ml. The method was accurate and sensitive, and could be used for the effective analysis of 3 higher fatty acid ethyl esters in Baijiu and for the daily analysis and detection of Baijiu in liquor enterprises.