利用电子鼻评价桃果实香气

为了明确不同桃品种资源果实香气差异,对桃果实香气评价和品质改良提供参考,本研究利用电子鼻系统对桃品种资源果实整果香气进行测定和区分。通过PEN 3.5电子鼻系统采集74份不同品种资源桃果实芳香成分并得到了不同传感器的响应值,采用主成分(PCA)、线性判别法(LDA)和负荷加载(LO)方法分析数据。LO分析结果显示,硫化氢(W1W)、氮氧化物类(W5S)、甲烷类(W1S)、芳香成分与有机硫化物(W2W)传感器对供试桃果实香气的评价起主要作用;结合PCA和区分度值表明白花水蜜、脆保、春冠、奉罐1号、菊黄和红肉桃1号与其他供试品种资源的香气区别较大;LDA可将不同果实生育期桃较好区分,长、中、短不同果实生育期桃甲烷类和芳香成分与有机硫化物传感器响应值差异显著(P<0.05);LDA可将硬肉类型(肉质绵)与其他4种肉质类型桃(不溶质、硬溶质、软溶质和硬质)区分开,且硬肉类型与其他4种肉质类型桃甲烷类传感器响应值差异显著(P<0.05);LDA无法区分不同肉色的桃,且各传感器响应值差异不显著。结果表明,生育期长短对桃果实香气有明显影响;硬肉类型桃香气较独特;不同肉色桃香气接近。

Evaluation of Aroma in Peach Fruit by Electronic Nose

In order to provide reference for peach fruit evaluation and quality improvement,the aroma components were evaluated using the electronic nose system PEN 3.5 in the fruit of 74 peach varieties.The response values from different sensors were recorded,followed by the analysis of PCA,LDA and LO.LO analysis results showed that four sensors W1W(hydrogen sulfide),W1S(methane compounds),W5S(nitrogen oxides)and W2W(aromatic components and organic sulfides)played a major role in the evaluation of the aroma of the tested peach fruit.PCA results and discrimination values indicated that the aromas of six varieties BaihuaS huimi,Cuibao,Springcrest,Fengguan 1,Ju Huang and Hongroutao 1 were observed with obvious differences with those of other tested varieties.LDA results were differing in peaches with different fruit development periods,i.e.,the methane compounds,aromatic components and organic sulfides were significantly different(P<0.05).With the LDA results,the peaches with flesh texture wooliness(soft)were identified with significant difference(P<0.05)from the other four flesh types(non-melting,hard melting,soft melting,and stony hard).However,LDA was not applied to discriminate flesh colors.The results indicated that:1)the period of fruit development represented a significant effect on the aroma of peach fruit,2)peaches with wooliness flesh texture have unique aromas,and 3)the aromas from peaches with different flesh colors are detected without a significant difference.