Does osmotic distillation change the isotopic relation of wines?

Abstract

Abstract. Currently partial alcohol reduction of wine is in the focus of research worldwide. There are several technologies available to achieve this target. These techniques are either based on distilling or membrane processes. Osmotic distillation, one of the possibilities, is a quite modern membrane process that can be used. During that process, wine is pumped in counter flow to water along a micro porous, hydrophobic membrane. The volatile components of the wine can permeate that membrane and are dissolved in water. The driving force of that process is the vapor pressure difference between the volatiles on the wine and water side of the membrane. The aim of this work was to determine if the alcohol reduction by osmotic distillation can change the isotopic relation in a wine. Can this enological practice change the composition of a wine in a way that an illegal water addition is simulated? Different wines were reduced by 2% alcohol v/v with varying process parameters. The isotopic analysis of the O 16/18 ratio in the wine were performed according to the OIV methods (353/2009) These analyses showed that the isotopic ratio is modified by an alcohol reduction of 2% v/v in a way that corresponds to an addition of 4-5% of external water.

The use of dextrose in winemaking

“…The variants 5-8 had a reduced alcohol content. Here the initial base wine was treated by osmotic distillation to reduce the alcohol level under the same parameters as explained in Schmitt et al 2014.…”

Alcohol Reduction by Physical Methods

“…A comparative study of the different physical methods helps to assess what technology is more gentle in terms of wine quality. Several sources report that a wine with an alcohol reduction by 2 vol.% is not differed from the initial wine [2,3,14,39,41,52,[56][57][58].…”