黄剑钊1,2，刘海纯1,2，李秀英1,2，郑学殷1,2，何敏恒1*,2
（1 广州检验检测认证集团有限公司，广东广州511447；
2 国家加工食品质量检验检测中心，广东 广州 511447）
摘要：为了建立一种快速测定液体乳中乳果糖含量的检测方法。该文通过单因素实验，以吸光度等为评价指标，综合考虑各种因素优化实验反应条件，并对实验方法进行方法学考察和回收率评价。结果显示，反应体系在69.12%硫酸溶液水解作用下，与3%半胱氨酸盐酸盐-0.06%色氨酸的显色剂进行46℃水浴反应2h，显色结果良好，乳果糖质量浓度在0mg/L～600mg/L 内具有良好的线性关系，回归方程为y=0.0033x+0.1745（R2=0.9992），检出限为5.20mg/L，精密度为0.79%～2.06%，样品加标平均回收率为96.48%～102.02%，相对标准偏差为0.53%～4.41%。结论表明该法经济高效准确，可适用于液体乳中乳果糖的定量检测。
关键词：紫外可见分光光度法；液体乳；乳果糖含量测定
Determination of Lactulose in Liquid Milk by Ultraviolet Spectrophotometry
HUANG Jian-zhao1,2，LIU Hai-chun1,2，LI Xiu-ying1,2，ZHENG Xue-yin1,2，HE Min-heng1*,2
（1 Guangzhou Inspection Testing and Certification Group Co.，Ltd.，Guangzhou 511447，China；
2 National Quality Inspection and Testing Center for Processed Foods（Guangdong），
Guangzhou 511447，China）
Abstract: To establish a easily and accurately method for the determination of lactulose in liquid milk. In this paper，the reaction conditions were optimized by single factor experiment with absorbance as the evaluation index，andvarious factors were considered comprehensively. The methodological investigation and recovery evaluation of the testmethod were carried out.The results showed that：the color was kept well under 69.12% sulfuric acid conditions and 3%cysteine hydrochloride-0.06% tryptophon，and water bath at 46℃ for 2h. Under the optimal conditions，the calibrationcurve was linear in the range of 0mg/L～600mg/L with a correlation coefficient of 0.9992 and the calculated linearequation was expressed as y=0.0033x+0.1745. The limit of detection was 5.20mg/L，while the precision was 0.79%～2.06%. The recovery rate of ranged from 96.48%～102.02%，with relative standard deviations of 0.53%～4.41%.Thismethod was economical，efficient and accurate for the quantitative detection of lactulose in liquid milk.
Key words: ultraviolet-visible spectrophotometry；liquid milk；the content determination of lactulose
中图分类号：TS252.7 文献标志码：A 文章编号：1007-7871（2023）05-0024-06
2023，Vol.26，No.5