The use of chitosan and an inactivated yeast to reduce the amount of sulfur dioxide in wine

Abstract

This study aims to evaluate the sulfur dioxide dynamics in two wines, dry white wine Fetească albă and dry red wine Fetească neagră made in Târnave vineyard, and to observe their evolution after application of Bactiless and Longevity to lower the level of SO₂. The wines from 2020 harvest were produced using traditional winemaking techniques. The experimental variants were: Control, Longevity (20, 30, 40, 0, and 40 g/hL) with Bactiless (20, 35, 50, 50 and 0 g/hL). For all the samples studied in this work, it was determined a decrease concentration of free and total sulfur dioxide. The best results obtained for the Fetească albă wine was the decrease of free SO₂ from 35.00 mg/L to 25.33±0.60 mg/L and total SO₂ from 120.50 mg/L to 117.50 mg/L by using 50 g/hL of Bactiless (CFAV4). For the Fetească neagră wine, the best results obtained were the decrease of free SO₂ from 32.50±0.29 mg/L to 14.83±0.18 mg/L and total SO₂ from 85.00±0.87 mg/L to 75.00±0.86 mg/L by adding 40 g/hL of Longevity and 50 g/hL of Bactiless (CFNV3). With an allowed SO₂ concentration, the evaluated wines maintained their varietal characteristics and organoleptic properties.