A Novel Approach for Controlling and Predicting Residual Sugars in Wines

Authors:
Preprint
Publisher website
Google Scholar
Abstract
Residual sugars (RS) in wine are the sugars that remain in a wine after fermentation is complete. In some wine styles, such as semi-dry wines, the accurate measurement of the RS concentration is critical for both qualitative and legislative reasons. Brix, measured by a simple refractometer, can give a good estimation of the RS concentration in the must, but during fermentation, the presence of alcohol leads to inaccurate sugar measurements. In order to measure the RS accurately, other more precise techniques are used, most of which are expensive or require professional skills. Therefore, novel approaches for rapid, easy, and practical measurements for estimating the sugar content were suggested over the years. However, the majority of these methods do not supply an actual measurement of RS but rather gives brix values, and those that measure RS involve special equipment, which is less relevant for small wineries. The RS values are critical for legislation purposes for deter-mining the wine style. In our study, we suggest a novel model for predicting and controlling the wine's residual sugar, by measuring the initial brix of the must before fermentation, and its density during fermentation. The model was created by measurements of actual residual sugars in natural and synthetic musts and showed high correlations. We used musts with brix values in the common range of fermented wines for our experiments. Thus, the re-gressions we present are practically all a winemaker needs in order to secure an accurate residual sugar in his final wine. By using the model, one can calculate the density values at which the fermentation will reach any desired residual sugar value, for any given initial brix level. This novel approach is a rapid and practical tool that could be very useful for the winemaker for estimating the density at which one should stop the fermentation to achieve specific levels of residual sugars in the wine before fermentation, saving time and reducing costs.

This publication has 30 references indexed in Scilit: