离子色谱-高分辨质谱法快速筛查乳制品中的酸度调节剂

建立了离子色谱-高分辨质谱(IC-HRMS)串联筛查乳制品中多种酸度调节剂的方法。乳制品样品用KOH溶液(pH调至7~8)提取,经Oasis MAX SPE柱净化,用Dionex IonPac AS11-HC柱(250 mm×4 mm)分离,Orbitrap检测器全扫描模式检测。以6种有机酸为例进行验证,在0.01~5.00 mg/L范围内线性相关系数均大于0.99。实际样品的加标回收率为74.3%~115.5%,相对标准偏差(RSD)为0.64%~4.81%(n=9)。将该法用于市售乳制品中酸度调节剂的筛查,在样品中可以筛查到苹果酸、柠檬酸、丁二酸、乳酸和己二酸。该方法快速、简便,可用于乳制品中多种酸度调节剂的定性筛查。

Rapid screening of acidity regulators in dairy by ion chromatography-high resolution mass spectrometry

A method for screening of acidity regulators in dairy based on ion chromatography-high resolution mass spectrometry technology (IC-HRMS) was set up. The dairy samples were extracted by KOH (pH 7-8) and Oasis MAX SPE column, and separated by a Dionex IonPac AS11-HC column (250 mm×4 mm). All the acidity regulators were detected by Orbitrap full scan mode. Taking six organic acids as an example, the calibration curves showed good linearities in the range of 0.05-5.00 mg/L, and the correlation coefficients (r) were higher than 0.99. By detecting the spiked samples, the recoveries were in the range of 74.3%-115.5% with the relative standard deviations (RSDs) between 0.64% and 4.81%. Malic acid, citric acid, lactic acid, succinic acid and adipic acid could be detected by IC-HRMS in the commercial dairy samples. The results indicate that the method is simple, rapid and suitable for the qualitative screening of acidity regulators in dairy products.