连续流动分析法测定葡萄酒中的总酸

Determination of total acid in wine by continuous flow analysis

目的建立连续流动分析法测定葡萄酒中总酸含量的方法。方法采用全自动连续流动分析仪测定葡萄酒中总酸,对蒸馏温度、进样时间进行优化。应用建立的方法对市售的新疆、山东、河北、宁夏4个产地的葡萄酒进行检测,并与国标方法进行了结果比对。结果葡萄酒中的总酸在2~10g/L范围内线性关系良好,回归系数r^2=0.9999,检出限为0.04 g/L,定量限为0.13 g/L。市售葡萄酒加标回收率在95.8%~104.9%之间,相对标准偏差小于1.0%(n=6),与国标方法比对结果无明显差异。结论该方法简便快捷,结果准确度高,相比国标中的电位滴定法,明显缩短了检测周期,提高了检测效率,可用于大批量葡萄酒中总酸含量的快速测定。

Objective To establish a method for the determination of total acid in wine by continuous flow analysis. Methods Total acid in wine was determined by automatic continuous flow analyzer and the distillation temperature and sampling time were optimized. The method was applied to detect wines from Xinjiang, Shandong, Hebei and Ningxia, and the results were compared with the national standard method. Results Total acid content in wine had good linear relationships in the range of 2–10 g/L, and the correlation coefficient r2 was 0.9999. The limit of the detection was 0.04 g/L and the limit of quantification was 0.13 g/L. The recoveries were 95.8%–104.9%, with the relative standard deviations was less than 1.0%(n=6). There was no significant difference between the results of comparison with the national standard method. Conclusion This method is simple in operation and high in accuracy. Compared with the potentiometric titration method in the national standard, this method obviously shortens the detection period and improves the detection efficiency, which can be used for rapid determination of total acid content in large quantities of wine.