饼干中脂肪的测定方法研究

Study on Determination Method of Fat in Biscuit

[目的]确定饼干中脂肪测定的酸水解温度和时间以及提取脂肪的次数,改变浸提剂,提高饼干中脂肪测定的效率和准确率。[方法]以不同比例的石油醚和无水乙醚为浸提剂,并结合水浴恒温振荡的方法对脂肪酸水解和提取过程进行优化。通过方法比对、质控样测定、实际样品分析,确定该优化方法的可行性。[结果]水浴温度为80℃,水解时间20 min,石油醚和无水乙醚比例1∶1,提取次数为3次,饼干中脂肪测定的效率和准确率最佳。与国标法比对,提高了脂肪的酸水解的效率,且该优化方法与国标法精密度均小于5%。同时采用该优化方法对质控样进行分析,结果显示,脂肪测定结果准确率高,其含量均在其特性值范围内(6.879%~8.663%)。[结论]该研究建立的方法提取效率高,精密度、准确性均满足检测要求,可应用于饼干中脂肪的测定。

[Objective]To determine the acid hydrolysis temperature and time for fat determination in biscuits and the number of times to extract fat,change the extractant,and improve the efficiency and accuracy of fat determination in biscuits.[Method]The different proportions of petroleum ether and anhydrous ethyl ether were used as extractant,and combined with the method of constant temperature shaking in a water bath to optimize the fatty acid hydrolysis and extraction process.The feasibility of this method was determined through method comparison,quality control sample determination,and actual sample analysis.[Result]The temperature of the water bath was 80℃,the hydrolysis time was 20 min,the ratio of petroleum ether and anhydrous ether was 1∶1,and the extraction times were 3 times.The efficiency and accuracy of fat determination in biscuits were the best.Compared with the national standard method,the efficiency of acid hydrolysis of fat was improved,and the precision of the optimized method and the national standard method were both less than 5%.At the same time,the optimized method was used to analyze the quality control samples,and the results showed that the fat determination results were highly accurate,and their contents were all within the range of their characteristic values(6.879%-8.663%).[Conclusion]The method established in this paper has high extraction efficiency,precision and accuracy meet the detection requirements,and can be applied to the determination of fat in biscuits.