Wine/Beer Smells like Nail Polish Remover – What happened?
Nail polish remover aroma is most likely caused by the ester ethyl acetate. As with all ester formation, higher fermentation temperature results in more ester production. Solvent-like aromas can also come from higher alcohols. Higher alcohol production is also increases with fermentation temperature. Solution: Limit fermentation temperature to the ideal temperature range of the selected yeast strain. That's the temperature of the must or wort, not the ambient temperature. Remember that heat is a by-product of yeast metabolism, so the temperature of the must or wort during active fermentation will be greater than the ambient temperature. Affixing a stick on thermometer to the fermentation vessel will allow for easy monitoring of fermentation temperature. The amount of ester and higher alcohols produced is dependent on the yeast strain. Some strains produce more than others. Solution: If your fermentation temperature is at the lower or middle ideal range for the selected yeast strain, consider changing the yeast strain. Some wild yeast strains are capable of producing large amounts of ethyl acetate. Solution: Keep everything clean and sanitized. Review sanitation procedures. Consider replacing plastic buckets and hoses if the problem persists. The use of non-food grade plastic fermenters or hoses can give a solvent-like aroma. Solution: Use only food-grade plastic fermenters and hoses. Underpitching (not pitching enough yeast) increases ester production. Solution: Pitch more yeast. If using dry yeast, use a minimum of 10 grams per 5-6 gallon batch, rehydrate and make a starter. Wyeast Activator packs are sufficient for 5-6 gallons without a starter for wine and ales. A starter, even with an Activator pack, is recommended for high gravity beers and lagers.