Study On Terpenoid Compounds And β-Glucosidase Change In Vidal Grape At Stages Of Ripping And Freezing

The variety aroma from fruit is considered to be very important composition for wine. Today, because of its typical and recognizable characteristics, it receives concern more and more.Terpenoid compounds change in Vidal grape at stages of ripping and freezing were studied using Headspace-Solid Phase Microextraction with Gas-Chromato-graphy Mass Spectrum (HS-SPME-GC-MS), and detected the enzymatic activities ofβ-Glucosidase in vidal grape. Finally, the Microorganism on grape skin were Selected by isolation and culture .The main results of the paper are as follows:1. The optimum results of SPME were extracted at 65℃for 20min.Linear equations of standard compounds were made and the CV of the repetition is less than 10.02%, and the recovery of the standard compounds on terpenoid compounds is 85.36%-101.21%, It showed that the method had good veracity and accuracy.2. This study detected eleven terpenoid compounds in vidal grape, lots of them have flowery and fruity aroma. The content of Geraniol which has peach aroma is higher than others. It is the typical aroma of ice wine. As the fruit ripening and freezing of the grape, the contents have changed and reached the maximum in October.3. The results showed that the optimal conditions of detecting the enzymatic activities were are 40℃, pH5.6, 0.05mol/L acetate buffer ,410nm and 10min of water bath time.4. By the isolation and culture of Microorganism on grape skin, twelve microbes which can produceβ-Glucosidase were Selected including six fungis and six Bacterias. The result is that the enzymatic activities of Bacillus pumilus and Fusarium are higher than others and have representative properties.