高效液相色谱-蒸发光散射法测定食品中的单糖、双糖、低聚果糖和糖醇

建立了食品中常用的木糖、果糖、葡萄糖、蔗糖、麦芽糖、乳糖、蔗果三糖、蔗果四糖、蔗果五糖、赤藓糖醇、木糖醇、甘露糖醇、麦芽糖醇等13种单糖、双糖、低聚果糖和糖醇的高效液相色谱同时分离检测的方法。该法采用NH₂色谱柱,以乙腈-水为流动相梯度洗脱,蒸发光散射检测器检测;13种糖在0.1~5 g/L内均具有良好的线性关系,检出限均在0.1 g/L以下,精密度(RSD)为2.69%~7.21%,回收率为96.1%~105.2%,结果较为理想。将该法用于实际样品检测,结果显示食品标签明示和实际成分相差较大。

Simultaneous determination of monosaccharides,disaccharides, oligosaccharides and sugar alcohols in foods by high performance liquid chromatography with evaporative light-scattering detection

A simple and efficient method was established based on high performance liquid chromatography (HPLC) to separate and detect thirteen analytes of monosaccharides, disaccharides, oligosaccharides and sugar alcohols (xylose, fructose, glucose, sucrose, maltose, lactose, 1-kestose, nystose, 1F-fructofuranosyl nystose, erythritol, mannitol, xylitol, maltitol) in foods. The separation was performed on an NH₂ column with the gradient elution of acetonitrile-water as the mobile phases. The analytes were detected by an evaporative light-scattering detector (ELSD). All the thirteen sugars had good linearities within 0.1-5 g/L with the correlation coefficients between 0.9901-0.9996. The limits of detection (LOD) were all less than 0.1 g/L. The precisions of the method expressed as RSDs were in the range of 2.69%-7.21%. The recoveries of the thirteen analytes spiked in real samples ranged from 96.1% to 105.2%. This method was applied to the actual sample testings and the results showed the food labels were greatly different from the actual compositions.