What is a common fault related to sulfur compounds in wine, and how does it present?

• A. H2S or sulfur off-odors (rotten egg, burnt rubber) or reductive aromas.
• B. No sulfur faults occur in wine.
• C. Sulfur faults produce only sweet aromas.
• D. Sulfur compounds enhance fruity aromas.

Answer: (A)

Sulfur-related faults are common in wine and show up as noticeable sulfur aromas when present in excess. The most typical fault is hydrogen sulfide, which smells distinctly like rotten eggs, and this can be accompanied by reductive notes such as burnt rubber, struck matches, or garlic. These aromas arise from sulfur compounds produced during yeast metabolism or from storage under low-oxygen, reductive conditions, often linked to inadequate yeast nutrition or stress during fermentation. They dull fruitiness and can make the wine feel shallow or unclean. While trace sulfur compounds can contribute certain fruity or smoky nuances in some wines at very low levels, a fault is defined by these off-putting sulfur aromas rather than any positive effect. Management focuses on preventing sulfur buildup through proper yeast nutrition, careful handling to avoid reductive conditions, and, if needed, fining with copper to bind sulfides.