Recently visited a local brewery. Normally, IMO, the brewery does a great job of brewing. I see Bière de Garde on the tap list. Haven’t had a Bière de Garde so I ask for a sample. Immediately, bringing the glass towards my mouth, I smell nail polish remover. Hmm… I don’t believe this is correct as I know acetone is a fault. Server says to me “What do you think?” I reply, “Acetone. I immediately smell acetone”. Server, “Huh?” I reply, “Acetone. Nail polish remover. Acetone or nail polish remover is normally considered as a brewing fault.” Server gives me a puzzled look and says “I don’t smell it.”
Having never brewed a Bière de Garde, is an acetone aroma normal for the style? Or, is this a fault as I was thinking?
According to 2015 BJCP, (24c) the aroma is described as:
“Aroma
Prominent malty sweetness, often with a complex, light to moderate intensity toasty-bready-rich malt character. Low to moderate esters. Little to no hop aroma (may be a bit spicy, peppery, or herbal). Paler versions will still be malty but will lack richer, deeper aromatics and may have a bit more hops. Generally quite clean, although stronger versions may have a light, spicy alcohol note as it warms.”
I would agree that the aroma of nail polish remover is not appropriate.
Of all the off flavors that can sometimes be appropriate in small amounts in certain styles, I can’t think of a single style or beer that would benefit from acetone.
Hot fermentation concerns, I would be willing to bet. Esterification of higher alcohols into Ethyl Acetate can also occur due to bacterial infection or yeast strain. In any event - not something you want in your beer.