Evaluation of Aroma Quality of Pork from Different Castrated Pigs Using an Electronic Nose

Immuno-castrated pigs(IC),surgically castrated pigs(SC) and entire male pigs(EM) were detected by an electronic nose(PEN3).15s,30s and 60s response values of electronic nose were analyzed by principal component analysis(PCA),linear discriminant analysis(LDA) and cross-validated discriminant analysis(CDA).The results showed that PCA was poorly discriminable due to the three groups almost overlapped.The odour of EM was significantly different from IC or SC and the odour of IC was similar to SC,so distinguishing and clustering effect of 15s response value obtained by LDA was better than others.CDA showed that the total accurate rate of 15s,30s and 60s response values were 90.0%,83.3%,66.7%,respectively,EM always had the highest accurate rate and IC was easily-confused with SC when the total accurate rate was low,moreover,the results showed that the IC and SC were similar.In a word,the results based on an electronic nose showed that the odour of IC and SC were similar,and both of them were different from EM.