Effect of microwave-ultrasonic synergistic aging technique on volatile flavor components of wine

In order to explore the efficient and appropriate aging method for wine, the effect of microwave-ultrasonic synergistic aging treatment on volatile flavor compounds of wine was investigated. Using fresh wine sample (S₁) without aging as a control, the volatile flavor components of wine samples (No. S₂-S₄) with different aging treatment were detected by gas chromatography-mass spectrometry (GC-MS), and the key flavor components were screened based on the relative odor activity value (ROAV) (1<ROAV<100), and the results were analyzed by principal component analysis (PCA). The results showed that a total of 205 volatile flavor substances were detected in wines with different aging treatments, and a total of 108, 134, 137 and 141 volatile flavor substances were detected in the samples from S₁ to S₄, and the key flavor substances were 14, 4, 18 and 14, respectively, among which esters, acids and alcohols were the main flavor substances in wines, and the types of volatile flavor substances increased after the synergistic aging of the wines with microwave-ultrasonic aging. The results of PCA showed that the difference between S₃ samples and fresh wine sample (S₁) was minimal, and PCA could effectively distinguish wine samples with different aging treatment based on volatile flavor substances. Under the conditions of ultrasonic power 260 W and microwave power 100 W, the optimal microwave-ultrasonic synergistic aging treatment for wine was aging at 40 ℃ for 20 min, and then at 15 ℃ for 20 min after 7 d.