核桃乳中掺大豆乳的鉴别研究

Identification of Adulteration in Walnut Milk Containing Soybean Milk

摘要:

建立了一种用高效液相色谱法检测核桃乳中掺有大豆乳的方法。样品用甲醇超声提取20 min，料液比为1:9 （体积比），在4000 r/min条件下离心20 min。使用Promosil C18（4.6 mm×150 mm，5 μm）色谱柱，以甲醇-水作流动相进行梯度洗脱，检测波长为258 nm。结果表明，通过对大豆异黄酮的检测，可以有效地鉴别核桃乳中是否掺有大豆乳；大豆苷和染料木苷的线性范围为0.3~200 μg/mL，大豆苷元和染料木素的线性范围0.1~150 μg/mL。线性相关系数在0.9968和1.0000之间，样品加标回收率为80.73~116.44%，相对标准偏差≤4.62% (n=5)，检测限为0.03~0.1 μg/mL，该方法快速、灵敏、简便易行。

Abstract:

A method for detection of adulteration in walnut milk containing soybean milk by high performance liquid chromatography was established. The extraction conditions were sample-methanol ratio 1:9 (V/V), ultrasonic time 20 min,and centrifugal time 20 min at 4000 r/min. The analysis was carried out with a column C18 (150 mm×4.6 mm, 5 μm) using methanol-water as gradient mobile phase at 258 nm. The results showed that walnut milk containing soybean milk was identified effectively through determination of soybean isoflavones. The linear ranges were 0.3~200 μg/mL for daidzin and genistin and 0.1~150 μg/mL for daidzein and genistein, respectively. The linear correlation coefficients were between 0.9968 and 1.0000. And the averrage recoveries were between 80.73% and 116.44%. The relative standard deviations (RSDs) were less than 4.62% (n=5) and the detection limits were 0.03~0.1 μg/mL. This method was fast, sensitive and simple.