title: Wine aroma improvement using a β-glucosidase preparation from Aureobasidium pullulans.
abstract: Microbial β-glucosidases have been used for the enhancement of wine aroma. Nevertheless, few enzymes are active in the conditions of winemaking. In this work, the production of a β-glucosidase by an Aureobasidium pullulans strain (Ap-β-gl) isolated from grape ecosystems was evaluated. The maximum enzymatic synthesis using submerged fermentation was after 96 h of growth in complex media containing 20 g/L of cellobiose as the sole carbon source. The crude enzyme (Ap-β-gl) showed optimal pH at 5.5 and two peaks of optimum temperature (at 45 and 70 °C). It showed a wide range of pH stability, stability at low temperatures, and tolerance to ethanol, showing suitable characteristics for winemaking conditions. The hydrolysis of glycosidic terpenes by Ap-β-gl was studied, and its ability to efficiently release free terpenols was demonstrated by gas chromatography/mass spectrometry. The enzymatic treatment notably increased the amount of monoterpenes, showing good prospects for its potential application for the development of aroma in wines.
authors.affiliation: Agricultural Sciences Institute (ICIAG), Uberlândia Federal University (UFU), 38405-303, Uberlândia, MG, Brazil. millabaffi@yahoo.com.br
authors.forename: Milla A
authors.initials: MA
authors.lastname: Baffi
authors.forename: Thaise
authors.initials: T
authors.lastname: Tobal
authors.forename: João Henrique Ghilardi
authors.initials: JH
authors.lastname: Lago
authors.forename: Maurício
authors.initials: M
authors.lastname: Boscolo
authors.forename: Eleni
authors.initials: E
authors.lastname: Gomes
authors.forename: Roberto
authors.initials: R
authors.lastname: Da-Silva
mesh_terms: D001203:Ascomycota / Q000201:enzymology*; D004795:Enzyme Stability; D005504:Food Analysis; D005511:Food Handling / Q000379:methods*; D009812:Odorants / Q000032:analysis*; D014920:Wine / Q000032:analysis* / Q000382:microbiology*; D001617:beta-Glucosidase / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D001617:beta-Glucosidase