离子色谱-积分脉冲安培检测法同时测定酱油中20种氨基酸和6种糖

Simultaneous determination of twenty amino acids and six carbohydrates in soy sauce by ion chromatography with integrated pulsed amperometric detection

建立了梯度淋洗-离子色谱-积分脉冲安培检测法同时测定酱油中20种氨基酸和6种糖的方法,通过对色谱柱温度、pH值、放置时间等实验影响因素的考察,探索出了适合26种组分测定的多级梯度淋洗条件。结果表明,当流速为0.25 mL/min , pH值在5.2~6.7,柱温在35 ℃时,26种组分在各自的浓度范围内具有良好的线性关系( r 2≥0.995)。除了谷氨酰胺、亮氨酸、异亮氨酸、蛋氨酸外,其他22种组分的检出限均小于0.03 mg/L;在0.20、0.50、2.00 mg/L 3个添加水平下,回收率为84.2%~109%, RSD为2.7%~7.8%。该方法高效、简便、灵敏、准确,可用于酱油中多种氨基酸和糖的同时测定以及掺假辨别技术研究。

A method of gradient elution ion chromatography with integrated pulsed amperometric detection for simultaneous determination of twenty amino acids and six carbohydrates in soy sauce was established. The effects of column temperature, pH value of solution, and standing time were studied, and then the suitable gradient elution conditions were found for the determination. In the conditions that the flow rate is 0.25 mL/min , pH value of solution is in the range of 5.2-6.7, temperature of column is 35 ℃, the linear relationships of the 26 components are good and the correlation coefficients are not less than 0.995. Except glutamine, leucine, isoleucine and methionine, the limits of detection ( S/N =3) of the other 22 components are less than 0.03 mg/L . The recoveries of the 26 components in soy sauce are 84.2%-109% at the spiked levels of 0.20, 0.50, 2.00 mg/L , and the relative standard deviations ( RSDs ) are in the range of 2.7%-7.8%. The method is efficient, easy, sensitive, and accurate for simultaneous determination of amino acids and carbohydrates in soy sauce, and can provide an effective research technique for adulterated soy sauce.