Improvement of volatile compounds and non-volatile metabolites in ‘summer black’ wines by controlled use of immobilized β-glucosidases

Immobilized β-glucosidase exhibits enhanced stability, reusability, and glycoside hydrolysis capabilities. Building on these advantages, this study investigates the impact of immobilized β-glucosidase on ‘Summer Black’ wine through comprehensive analysis of volatile compounds and non-targeted metabolomics. The results showed that both the addition of free β-glucosidase (FGL) and immobilized β-glucosidase (IGL) before fermentation significantly increased the anthocyanin concentration in the wines (p < 0.05). Furthermore, the FGL and IGL treatment significantly increased the total content of volatile compounds, especially enhancing the levels of higher alcohols and esters (p < 0.05). Immobilized β-glucosidase hydrolyzed more glycoside-bound substances, released more terpenoids and benzene derivatives, and produced more esters during fermentation. In terms of differential metabolites, both β-glucosidase treatments were superior to the control, with the IGL treatment was more active on glycolysis and TCA cycle biosynthesis and metabolism than FGL. IGL treatment significantly reduced the shikimic acid level and increased the dipeptides levels, and then promoted the synthesis of aromatic amino acids. Reduced most vitamins (V B3 , V B6 , V B7 , V C , V H , V K1 ) content de-promoted yeast metabolism in wine. Additionally, IGL treatment also up-regulated most of phenolic compounds such as flavonoid, monomeric and polymeric flavanols, and phenolic acids. These conclusions contribute to increasing the application of immobilized β-glucosidase in wine and also provide an effective means for winemakers to precisely control the winemaking process and produce different types and styles of wines. • Novel controlled-fermentation of table grape by immobilized β-glucosidase is proposed. • The addition of β-glucosidase improved anthocyanin, color, volatiles and metabolism. • Immobilized β-glucosidase promotes more terpenes, benzene derivatives, and metabolism. • Different ways of adding β-glucosidase could produce wines with different styles. • The addition of immobilized β-glucosidase produced wines of the highest quality.