Comparative study of different commercial enzymes on release of glycosylated volatile compounds in white grapes using SPE/GC–MS

Glycosides represent a large source of potential flavor in grape must. Commercial preparations enzymes with glycosidase activity are commonly employed to enhance wine aroma. In this study, we conducted an evaluation of twelve commercial enzymes to assess their effectiveness in releasing volatile compounds from their conjugated forms in a white grape must under laboratory conditions by solid-liquid extraction (SPE) and gas chromatography-mass spectrometry (GC-MS). In this laboratory-level experiment, regardless of the enzymes used, the total concentration of volatile compounds was not statistically affected by the treatments. While the total concentration of volatile compounds remained largely unchanged, four specific volatile groups were significantly affected by the enzyme treatments: acids, alcohols, C₁₃-norisoprenoids, and terpenes. The results also revealed a significant effect of commercial enzymes on individual compounds, which led to a notable increase in the concentration of twenty-one aroma compounds, mainly terpenes. Rapidase Revelation Aroma and Enozym Extra Aroma emerged as the most powerful ones on the must's volatile composition with important ability to release higher concentrations of essential varietal aroma compounds, particularly terpenes and C₁₃-norisoprenoids.