高效阴离子交换色谱-脉冲安培检测法分析啤酒和麦汁中的糖

建立了高效阴离子交换色谱-脉冲安培检测(HPAEC-PAD)同时测定单糖、二糖和多种低聚糖的方法。采用水、0.25 mmol/L NaOH溶液和1 mol/L NaAc溶液三元梯度淋洗,在CarboPac PA-100色谱柱上,11种糖在40 min内达到良好分离;采用积分脉冲安培检测方法,无需对样品进行复杂的前处理或衍生反应便可直接检测。11种糖的检出限(S/N=3)在13～88 pg范围内。将该方法用于啤酒和麦汁样品中单糖、二糖及低聚糖的分析取得了很好的结果,样品中的加标回收率为81%～107%。

Analyse of sugars in beer and wort using high performance anion-exchange chromatography coupled with pulsed amperometric detection

The method of the simultaneous and direct analysis of eleven sugars, including monosaccharides, disaccharides and oligosaccharides, was established using high performance anion-exchange chromatography (HPAEC) coupled with pulsed amperometric detection (PAD) using an Au working electrode and a pH-Ag/AgCl reference electrode. The separation was accomplished on a CarboPac PA-100 column by using gradient elution consisting of water, 0.25 mol/L NaOH and 1 mol/L NaAc as mobile phase at a flow rate of 0.25 mL/min. Under these conditions, glucose, fructose, sucrose, maltose, isomaltose, maltotriose, isomaltotriose, maltotetraose, maltopentaose, maltohexaose and maltoheptaose were separated in 40 min. Then sugars were detected directly with PAD method without any derivatization reaction, and there was no need to employ complicated pretreatment procedures to the samples before analysis. The detection limits (S/N=3) for the sugars were 13-88 pg. The proposed method was applied for the determination of the 11 sugars in beer and wort samples satisfactorily, with the spiked recoveries of most sugars ranging from 81% to 107%. In addition, some potential transition mechanism of the sugars during the brewage procedure can be educed from the comparison of sugar contents between beer and wort.