以牛肉为研究对象,采用电子鼻技术考察实验参数——顶空空间、样品质量和顶空生成时间对电子鼻传感器响应信号的影响。选取传感器信号峰值和稳定值进行分析,通过方差分析观察单个传感器以及整个传感器阵列对不同参数的响应情况,同时结合主成分分析、线性判别分析得出较佳顶空空间为500 mL、样品质量为25 g、顶空生成时间为5 min,并应用此参数进行电子鼻对储藏0、3、5、7、10、12、14 d牛肉样品的检测,逐步判别分析正确率为98.57%。
The effects of beaker volume,sample weight and headspace-generation time on the response of a PEN2 electronic nose(e-nose) were studied.Both the peak and final stable responding points of sensors were extracted.Principle component analysis(PCA),linear discriminant analysis(LDA) and analysis of variance(ANOVA) were employed to analyze the responding of each sensor as well as the whole sensor array,and the optimum parameters(500 mL beaker volume,25 g sample mass,5 min headspace-generation time) were acquired for later beef storage time detection.The difference in volatile profiles of beef samples of seven different storage times(0,3,5,7,10,12 and 14 d) was confirmed.The stepwise linear discriminant analysis(Step-LDA) results showed that the correct rate was 98.57%.