固相微萃取-气相色谱法结合感官评价建立液态乳在物流中酸败的预测方法

Predict liquid milk quality during the progress of logistics by Solid Phase Microextraction-Gas Chromatography and sensory evaluation

乳制品在物流过程中可能受环境或人为原因导致酸度增加,产生异味,质量下降,需要一种方便精准的方法来检测乳制品质量。本文利用固相微萃取和气相色谱法结合感官评价建立检测和预测液态乳制品在物流过程中酸败的分析方法。由评审员根据感官评定参考标准,对牛奶样品进行评分;通过固相微萃取和气相色谱法(Solid Phase Microextraction and Gas Chromatography,SPMEGC)测定牛奶中的短链游离脂肪酸(free fatty acids,FFA)(C4-C12)浓度和酸度值(Acidity value,ADV),检验FFA浓度和ADV值与感官评估的相关性。使用逐步多元线性回归将不同酸度样品的FFA和ADV数据进行回归分析。结果表明短链脂肪酸浓度和酸度值与酸度感官评分存在相关性;逐步回归确定牛奶中酸败风味强度方程,对19种商业液态乳制品进行酸度分数测定时,一种样品发生明显地酸败,显示了模型的预测能力,对于所测试的样本,预测准确率为100%。本研究通过固相微萃取-气相色谱法结合感官评价建立的预测液态乳在物流中酸败的方法快速、准确,适合评估液态乳制品的质量。

During the process of logistics dairy products may lead to increased acidity, odor and decreased quality due to the environmental or human causes, so we have the need for a convenient and accurate method to detect the quality of dairy products. The analytical method for detecting and predicting the rancidity of liquid dairy products during the process of logistics was established by using solid-phase microextraction and gas chromatography combined with sensory evaluation. The assessors rated the milk samples according to the sensory, evaluation reference standard;The concentrations of short chain free fatty acids （FFA） （C4-C12） and acidity （ADV） in milk were determined by solid-phase microextraction and gas chromatography （SPME-GC） to test the correlation between FFA concentrations and ADV values and sensory evaluation. Regression analysis was performed on FFA and ADV data for different acidity samples using stepwise multiple linear regres- sion. There was a correlation between short chain fatty acid concentration and acidity value and acidity sensory score;Gradual regression to de- termine the strength of the rancid flavor of milk equation,When acidity scores were measured on 19 commercial liquid dairy products, one of the samples was significantly ranciferous and showed the predictive power of the model, with a predicted accuracy of 100% for the samples tested.In this study, the method for predicting the rancidity of liquid dairy products during the process of logistics by solid-phase microextraction-gas chromatography combined with sensory evaluation is rapid and accurate and suitable for evaluating the quality of liquid dairy products.