VOLATILE SULFUR COMPOUNDS — IMPACT ON “REDUCED SULFUR” FLAVOR DEFECTS AND “ATYPICAL AGEING” IN WINE

Volatile sulfur (S-)-containing compounds have a significant role in the flavor of wines. This is related to their high volatility, reactivity and potency at very low concentrations. Some of the S-substances are necessary for wine quality, while others are the cause of strong objectionable flavours (rotten eggs, cooked cabbage, cauliflower burnt rubber etc.), even at extremely low concentrations (e. g. H2S, methanethiol, ethanethiol). Certain thiols contribute to the typical sensory impression of grape varieties like Chenin Blanc, Sauvignon Blanc, Scheurebe etc.. In wines produced from these varieties very varied aromatic nuances are noticeable (blackcurrant, passion fruit, boxtree, grapefruit etc.). Organic and inorganic S-containing substances and pesticides in grapes and musts affect the formation of volatile S-compounds. Other factors are the nutrient content in grapes and musts, the yeast metabolism during fermentation and fermentation parameters.