A Novel Extracellular β-Glucosidase from Trichosporon asahii: Yield Prediction, Evaluation and Application for Aroma Enhancement of Cabernet Sauvignon
Article first published online: 18 JUL 2012
© 2012 Institute of Food Technologists®
Journal of Food Science
Volume 77, Issue 8, pages M505–M515, August 2012
How to Cite
Wang, Y., Xu, Y. and Li, J. (2012), A Novel Extracellular β-Glucosidase from Trichosporon asahii: Yield Prediction, Evaluation and Application for Aroma Enhancement of Cabernet Sauvignon. Journal of Food Science, 77: M505–M515. doi: 10.1111/j.1750-3841.2012.02705.x
- Issue published online: 3 AUG 2012
- Article first published online: 18 JUL 2012
- MS 20111075 Submitted 9/7/2011, Accepted 1/31/2012.
- aromatic precursor;
- production improvement;
- Trichosporon asahii;
- wine aroma
Abstract: The production and application of novel β-glucosidase from Trichosporon asahii were studied. The β-glucosidase yield was improved by response surface methodology, and the optimal media constituents were determined to be dextrin 4.67% (w/v), yeast extract 2.99% (w/v), MgSO4 0.01% (w/v), and K2HPO4 0.02% (w/v). As a result, β-glucosidase production was enhanced from 123.72 to 215.66 U/L. The effects of different enological factors on the activity of β-glucosidases from T. asahii were investigated in comparison to commercial enzymes. β-Glucosidase from T. asahii was activated in the presence of sugars in the range from 10% to 40% (w/v), with the exception of glucose (slight inhibition), and retained higher relative activities than commercial enzymes under the same conditions. In addition, ethanol, in concentrations between 5% and 20% (v/v), also increased the β-glucosidase activity. Although the β-glucosidase activity decreased with decreasing pH, the residual activity of T. asahii was still above 50% at the average wine pH (pH 3.5). Due to these properties, extracellular β-glucosidase from T. asahii exhibited a better ability than commercial enzymes in hydrolyzing aromatic precursors that remained in young finished wine. The excellent performs of this β-glucosidase in wine aroma enhancement and sensory evaluation indicated that the β-glucosidase has a potential application to individuate suitable preparations that can complement and optimize grape or wine quality during the winemaking process or in the final wine.
Practical Application: The present study demonstrated the usefulness of response surface methodology based on the central composite design for yield enhancement of β-glucosidase from T. asahii. The investigation of the primary characteristics of the enzyme and its application in young red wine suggested that the β-glucosidase from T. asahii can provide more impetus for aroma improvement in the future.