水蜜桃采后贮藏期间风味物质及质构特性的研究

Changes on flavor substances and the texture properties of peach during postharvest storage

以"霞晖6号"水蜜桃为试验材料,置于20℃、相对湿度为70%～75%的条件下贮藏,分别在0、1、2、3、4、5、6 d采用质地多面分析(TPA)测试法、顶空固相微萃取﹣气质联用(HS﹣SPME/GC﹣MS)和电子鼻技术测定桃果实采后贮藏期质构特性及风味物质。结果表明,桃果实采后硬度、胶黏性随贮藏时间的延长呈下降趋势,咀嚼性和弹性先下降后上升。桃果实在采后贮藏期内,利用HS﹣SPME/GC﹣MS技术共检测出58种香气物质,主要是醛类、酮类、酯类、内酯类、醇类、酸类和烃类化合物。从主成分分析(PCA)和线性判别式分析(LDA)结果可知,电子鼻技术可以很好地区分开不同贮藏期的桃子。综合评价得出,桃果实的质构特性及挥发性风味物质的种类、含量会随着贮藏时间而发生变化。质构仪测得的力学指标结合GC﹣MS及电子鼻所测数据可以准确地反映果实的品质特性。

Texture properties and flavor substances of peach fruits(Xiahui No.6)during postharvest storage were investigated by texture profile analysis(TPA),headspace solid phase micro-extraction gas chromatography mass spectroscopy(HS-SPME/GC-MS)and electronic nose technology at 0,1,2,3,4,5,6 d.The peaches were stored at 20℃,and the relative humidity was 70%~75%.The results showed that the hardness and gumminess of peaches decreased during storage.Chewiness and springiness decreased to the minimum levels and then exhibited an increase.58 kinds of flavoring compounds,mainly containing aldehydes,ketones,esters,lactones,alcohols,acids and hydrocarbons,were detected by HS-SPME/GC-MS during storage.From the results of principal component analysis(PCA)and linear discrimination analysis(LDA),the electronic nose technology can clearly and rapidly distinguish the peaches in different storage periods.According to the comprehensive evaluation,the texture properties of peaches,the types and contents of volatile flavor substances will change with storage time.The mechanical parameters measured by texture analyzer combined with the data measured by GC-MS and electronic nose can accurately reflect the quality characteristics of the fruit.