Influence of enzymatic treatments on white wine composition

E.C Scutaraşu,R Oprean,L.C Colibaba,N Katalin,C.E Luchian,V.V Cotea,M Niculaua,P Roca

doi:10.1051/bioconf/20191502032

Abstract

Most biochemical reactions involved in the wine-making process are catalyzed by enzymes. The use of enzymes of exogenous origin in wine production is due to the numerous technological and economical advantages demonstrated over time in the winemaking process. Understanding the important role played by enzymes in wine making technology contributes to the development of optimization strategies for the production process to improve the final quality of the wine. In order to accomplish this study, the influence of five oenological preparations with pectolytic and β-glucosidases enzymes types on the volatile compounds of white wines obtained from Fetească regală variety was analyzed by monitoring their evolution during the alcoholic fermentation to the final product. Wine samples have been physically and chemically analysed (pH, acidity, alcoholic strength, density, malic acid, lactic acid, sugar content, SO2, total dry extract and non-reducing extract) according to OIV Standards. Separation and identification of flavor compounds was performed using an Agilent 7890 gas chromatograph coupled to a 5975 C inert XL EI/CI MSD spectrophotometer. The organoleptic evaluation of wines was made according to a wide range of sensory descriptors. An important evolution of volatile compounds during fermentation was observed, depending on the type of enzyme administered, compared to the control sample. Enzymatic treatments did not significantly affect the physico-chemical composition of the wines obtained. The chromatic parameters of the wine samples varied according to the type of enzyme applied. The results of the study showed a significant influence of the enzymes on the organoleptic characteristics of the wines. Therefore, the aromatic quality of a wine is directly proportional to the chemical composition of the grapes and to the technology.

Highlights

Enzymes are biological catalysers used in winemaking technology for their numerous advantages on the product quality
Five commercial enzymes based on pectolytic and β-glucosidases activity were added to musts before alcoholic fermentation, contributing to the release of aroma compounds (Endozym Thiol®, AEB – V1; Endozym β -Split®, AEB – V2; Zymovarietal aroma G®, SODINAL – V3; Endozym Ice®, AEB – V4; Zimarome®, BSG WINE –V5 and no enzyme– V6), at doses of 3 g/hL and 3 mL/hL respectively. 6 variants were obtained
Enzymatic treatments determine an increase in the total amount of volatile compounds compared to control samples

Summary

Introduction

Enzymes are biological catalysers used in winemaking technology for their numerous advantages on the product quality These compounds may come from indigenous microflora of grapes, yeasts or other bacteria correlated with wine cellar, vinification conditions or vineyard [1]. Pectinolytic enzymes have the ability to cleave long pectin chains into shorter and more soluble chain segments, that facilitate pressing operation of the grapes and clarification of musts, enhace the extraction of color and aroma compounds and facilitate the filtration of resulted wine. These enzymes can facilitate the stabilisation of the wines, due to the enzymatic hydrolysis of the protein into smaller molecules, containing more nitrogen. Understanding the important role of enzymes in winemaking technology contributes to the development of strategies to optimize the production process, improving the wine’s composition and its sensory characteristics [7]

Methods

Results

Conclusion