A VERY EFFICIENT BETA-GLUCOSIDASE CATALYST FOR THE HYDROLYSIS OF FLAVOR PRECURSORS OF WINES AND FRUIT JUICES

Candida molischiana 35M5N alpha-glucosidase was immobilized to Duolite A-568 resin. Higher immobilization efficiency (86%) was achieved with citrate-phosphate buffer (0.1 M) at pH 4. The study of the immobilize d beta-glucosidase demonstrated that the physicochemical properties we re similar to those of the free enzyme. Free and immobilized beta-gluc osidase were used to treat muscat wine and apricot fruit juice. GC-MS analysis indicated a significant increase in the flavor compounds nero l, geraniol, linalool, 2-phenylethanol, and benzyl alcohol in the musc at wine and linalool, alpha- and gamma-terpinene, alpha-terpineol, 2-p henylethanol, and alpha-pinene in the apricot fruit juice. The immobil ized beta-glucosidase was found to be very stable under fruit juice or wine conditions and could be used repeatedly for several hydrolyses o f bound aroma. The efficiency of this experimental catalyst was succes sfully tested with several fruit juices and wines containing various a mounts of precursors.