Water in my beer!

[CBMbrewer]

I brewed 9 gallons of IPA about three weeks ago. It fermented in my conical in a temp controlled upright freezer. On thursday I began to cold crash so I replaced the airlock with a tube running down into a jar of water sitting on the floor of the freezer. I thought I had made the tube long enough but the temperature difference created so much negative pressure in the conical that about 20 to 25 oz of water got sucked in. The water wasn't dirty but it certainly wasn't sanitized. The beer had been done fermenting since monday and the abv is at 7.2%. I would guess that there is enough alcohol in the beer to prevent an infection and it has been at 38F since thursday night and will remain at that temp until it has all been drank. I will be kegging it. Do you guys think it might develop an infection? Could/should I add some potassium metabisulfite to prevent anything from multiplying and ruining the beer?

 

[cluckk]

Temp, pH and ABV makes it unlikely. If you are worried about the water from an airlock getting sucked back during cold crashing try one of the S-shaped airlocks. They are designed to bubble both ways so you don't get liquid sucked back into the beer.

 

[CBMbrewer]

Thank you Cluckk. Piece of mind is wonderful! I will definitely take your advice and switch airlock types.