Immobilized Endo-β-glucosidase Enriches Flavor of Wine and Passion Fruit Juice

Aspergillus niger endo-β-glucosidase was immobilized to acrylic beads as well as to corn stover cellulose particles. The efficiency of the immobilization at pH 6.5 to the acrylic beads, with respect to activity, was higher than that to the cellulose but still low (10%). However, higher immobilization efficiency for cellulose (30%) was achieved at pH 4.5. The thermal stability of the enzyme was improved by its immobilization in both methods. Free and immobilized endo-β-glucosidases were used to treat Muscat Roy wine and passion fruit juice (pH 2.45). GC-MS analysis as well as sensory evaluation indicated a significant increase in flavor compounds, monoterpene alcohols, and linalool oxides in the wine and linalool, benzyl alcohol, and benzaldehyde in the passion fruit juice. The precursor of the benzaldehyde is a cyanogenic glycoside as evident from the evolution of cyanide followed by the enzymatic treatment.