纳米薄膜真空包装杏鲍菇在贮藏中的风味品质变化

Changes of Flavor and Quality of Pleurotus eryngii Packed with Nano Film in Vacuum during Storage

为延长杏鲍菇在纳米薄膜真空包装的保质期,将杏鲍菇的采后鲜品置TiO_(2)和SiO_(2)复合纳米薄膜保鲜袋,于0.07 MPa真空预冷至4℃以下,2℃冷库中贮藏;定期采样测试游离氨基酸,并采用HS-SPME-GC-MS测试挥发性风味物质,分析三个贮藏期内风味品质的动态变化。结果表明:共检测到17种游离氨基酸,包含7种必需氨基酸,在第0 d氨基酸总量1196.15 mg/100 g,第20 d为1425.26 mg/100 g,第40 d为1629.77 mg/100 g,鲜味氨基酸含量不断增加;共检测到36种挥发性物质,其中醇类、酯类是主要成分占90%左右;通过分析挥发性物质种类的韦恩图及相对含量热图、关键挥发性物质的主成分PCA载荷图,结果表明杏鲍菇贮藏0、20和40 d,样品挥发性风味成分的种类和含量差异明显,醇类逐渐增加,分别占比为33.49%、72.14%、77.25%,酯类逐渐减少,分别占比为56.56%、22.23%、9.76%。通过香气特征QDA分析,三个贮藏期的香气特征分别为蘑菇香、花果香和刺鼻脂肪味,乙醇与1-戊醇可作为表征杏鲍菇腐败程度的标记物。采用纳米薄膜真空包装贮藏的杏鲍菇鲜品,能较好的保持风味品质,延长贮藏保鲜期。

In order to extend the shelf life of Pleurotus eryngii in nanofilm vacuum packaging,the fresh postharvest Pleurotus eryngii was placed in TiO_(2) and SiO_(2) composite nanofilm fresh-keeping bags,the sample was precooled to below 4℃under 0.07 MPa and then stored at 2℃.In order to evaluate the dynamic changes of flavor qualities during storage,the free amino acids and the volatile flavor compounds were analyzed at 0,20,and 40 days.The results showed that 17 free amino acids were detected,including 7 essential amino acids.The total amount of amino acids was 1196.15 mg/100 g,1425.26 and 1629.77 mg/100 g on day 0,20 and 40,and the content of delicious amino acids increased with storage time.A total of 36 volatile compounds were detected.The alcohols and esters were the two main components,which accounting for about 90%of the total volatile compounds content.The Venn diagram of volatile compounds,the heat diagram of relative content,and the PCA load diagram of key volatile substances revealed that the types and contents of volatile flavor compounds of Pleurotus eryngii changed significantly(P<0.05)during storage.On 0,20 and 40 days,the content of alcohols accounting for 33.49%,72.14%and 77.25%of the total volatile flavor compounds,while the values of esters were 56.56%,22.23%and 9.76%.According to the QDA analysis of aroma characteristics,the aroma characteristics of the three storage periods were mushroom flavor,flower and fruit flavor,and pungent fat flavor,respectively.Ethanol and 1-pentanol could be used as markers to characterize the degree of Pleurotus eryngii corruption.Fresh Pleurotus eryngii vacuum-packed in nanofilm could better maintain their flavor qualities and prolong their storage period.