非线性化学指纹图谱法检测羊奶粉中掺杂的糊精

Determination of Dextrin Content in Goat Milk Powder by the Nonlinear Chemical Fingerprint Method

摘要:

采用“硫酸-丙二酸-溴酸钠-溴化钠-硫酸铈铵”为振荡体系，利用非线性化学指纹图谱法测定羊奶粉中掺杂的糊精含量。先向羊奶粉中掺入不同量的糊精，配成掺杂糊精的羊奶粉标样，每份羊奶粉标样的总量为0.7 g。通过非线性化学指纹图谱法对羊奶粉标样进行测定，运用最小二乘法，拟合出其诱导时间相对于羊奶粉中掺杂糊精含量之间的一元线性关系，可求出羊奶粉中掺杂的糊精含量。实验表明该方法可以达到以下指标：当羊奶粉中掺杂的糊精含量在0~30%范围内时，糊精含量与诱导时间值线性关系良好，相关系数R2为0.9991~0.9998，回收率为94.00%~108.75%，RSD为0.31%~1.96%，检测范围为0~0.30 g/g，检出限为8~9.3 mg/g。方法准确度高，操作简单，是一种切实可行的测定羊奶粉中掺杂糊精的方法，也可作为复杂样本中其它成分定量分析借鉴的方法。

Abstract:

The content of dextrin in goat milk powder could be determined rapidly by the nonlinear chemical fingerprint method with sulfuric acid, malonic acid, ceric ammonium sulfate, sodium bromate, and sodium bromide as the oscillating system. Different amounts of dextrin were added to goat milk powder to prepare standard samples of adulterated goat milk. The total weight of each goat milk powder standard sample was 0.7 g. The nonlinear chemical fingerprints of these standard samples were obtained, and the least square method was used to fit the linear relationship between the induction time and the content of dextrin in the standard samples. Subsequently, the content of dextrin in the adulterated goat milk powder could be calculated. The results showed that within 0~30% range of dextrin content in the adulterated goat milk powder, the dextrin content and the induction time value had a good linear relationship. The correlation coefficient ranged from 0.9991~0.9998, the recoveries were between 94.00%~108.75%, and the relative standard deviations (RSDs) were in the range of 0.31%~1.96%. The determination range of the content of dextrin in goat milk powder was from 0~0.30 g/g, and the detection limits were in the range of 8~9.3 mg/g. The method is simple to use and has a good accuracy. It is a practical and feasible method for determining the content of dextrin in goat milk powder, and can be a potential method to quantitatively analyze other components in complex samples.