Brewed up a batch of wort yesterday and it all went well. Good sanitation, quick cool down, and yeast activated. Set up the carboy in a controlled temp room (74) and fermentation started within 4 hours and really took off. All good. Took the wife out for dinner and a movie - when I got home found the airlock and stopper had shot out of the carboy. Consulted this site and hooked up a blow off tube. Everything is going OK now - still bubbling away like mad. I don't know how long the wort was exposed. There was and continues to be a thick head of Krausen.

Does the exposure mean my wort is ruined? How can I tell?

Any advice will be helpful...thanks...Let me know (I'll be painting the ceiling)

1 Answer 1


The beer should be fine. With the yeast active like it is, bacteria and wild yeast would have a very hard time establishing a foothold. Brief exposure to the atmosphere should not affect your beer.

  • During vigorous fermentation like that, it's highly unlikely the wort was even exposed to the atmosphere. The CO2 produced during fermentation likely had already formed a layer of gas on top. Without external influences, it's unlikely that this layer was disturbed, even with the airlock and stopper popping off. I'd keep the blow off tube for the first day or two and then switch back to the airlock. Your beer is most likely fine.
    – rjbergen
    Jan 4, 2015 at 17:39

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.