摘要
利用氨基酸与茚三酮反应显色的原理,建立了茚三酮比色法测定湘西腊肉中甘氨酸含量。方法优化了溶液pH、显色剂用量、乙醇用量、加热温度、加热时间和冷却时间对茚三酮比色法定量检测甘氨酸的影响。结果表明,样品前处理最优条件为:溶液pH值7.0,显色剂用量2.0 mL,乙醇用量5.0 mL,水浴温度和时间分别100℃、15 min,冷却时间10 min。以甘氨酸为标准溶液,在568 nm波长下测定样品溶液的吸光度,根据朗伯-比尔定律计算样品中甘氨酸含量。甘氨酸测定的线性范围为0.14 ug/mL^50 ug/mL,检出限为0.14 ug/mL,线性相关系数达0.9994。甘氨酸的加标回收率为99.1%~100.5%,测量结果的相对偏差为0.3%~1.5%(n=6)。该方法简便、廉价、快速、准确,可用于湘西腊肉甘氨酸含量的测定。
A method was developed for the determination of Glycine in Xiangxi bacon by Ninhydrin colorimetric method.Key parameters that affect impurity removal and recovery of samples were optimized including pH value,the volume of chromogenic agent,the volume of ethanol,heating temperature,heating time and cooling time.The results showed that the optimal conditions for sample pretreatment were:pH value 7.0,dosage of colorizer 2.0 mL,dosage of ethanol 5.0 m L,temperature and time of water bath 100℃,15 min,and cooling time 10 min,respectively.The absorbance of the sample solution was measured at the wavelength of 568 nm with glycine as the standard solution.The linear range of glycine determination was 0.14 ug/mL^50 ug/mL,the detection limit was 0.14 ug/mL,and the linear correlation coefficient was 0.9994.The recovery of glycine was 99.1%~100.5%,and the relative deviation of the measured results was 0.3%~1.5%(n=6).The method was simple,rapid,low-cost and applicable for the determination of Glycine in Xiangxi bacon.
作者
邓湘波
邓湘平
DENG Xiangbo;DENG Xiangping(Chenzhou fOod and drug inspection center,Hunan Chenzhou 423000,China;Suxian food and drug administration,Hunan Chenzhou 423000,China)
出处
《食品工程》
2019年第4期55-59,共5页
Food Engineering
