Another air lock question

I have a similar question to one posed earlier by talenos... My brother wanted to try out brewing so I lent him my equipment, went and got an extract kit with him and showed him the gist of brewing the wort, adding to primary ect.... Well I left him with some pretty simple instructions to finish the brew (transfer to secondary, bottling ect..) when I left and went back home (about 4 hours away from where he lives). I showed him how occasionally he may have to put in a blow off tube if the krausen gets too high in the fermenter. He decided he was just going to put in the blow off tube before too much krausen, just in case, however he did not put the other end in some water or sanitizing solution. The fermentation had been going for about one day already before he put the tube in, so my long-winded question is.... do you all think I can have him just transfer to secondary, put in a normal air lock and see if it'll turn out alright?. The blow off tube was left out for a week before i called him to see how it was going. The thing I'm worried about is contamination and too much oxygen getting into fermentation vessel. Thanks in advance for any advice, and thanks for those who took the time to read all of this novel.

Well, there's really only one way to find out. I would think that infection is somewhat likely (and if that is the case, and your fermenter is plastic, you're going to have to kiss it goodbye) but there's still hope. I don't secondary (with very few exceptions) but have him taste it when he racks the beer. If it tastes okay, it'll probably be fine in the end.

Good luck.

+1 on the tasting. It will be your best indication of whether or not it's salvageable. Some would also argue that you not dump the beer under any circumstance and let this thing age out and see how it tastes. Good luck in any case.

yeah I was going to have him give it a taste just to see if it is even palatable and still rack to secondary. I guess my next question is: even if its not contaminated could fermentation have even gone on well without the proper air lock? I would imagine the environment in the fermenter would be to aerobic for proper fermentation to take place. I guess we will just have to wait and see what happens. Thanks for the input everyone.

fermentation produces lots of CO2, which initially will keep the oxygen (and contamination) from being an issue by provided positive pressure to keep anything from going into the blow off tube.

Even once fermentation has died down, CO2 is heavier than air, so it will tend to stay put over the top of the beer if you don't agitate it or slosh it around or anything. there's certainly an increased chance for oxidation or contamination by doing what he did, but it's probably fine. open fermentation used to be very common and is still used by some places even today.

Even without liquid for the blowoff tube to bubble into, the chance of contamination is still pretty remote - the CO2 pushing out of the tube makes it pretty difficult for anything to get back in. I would have him proceed as normal and assume that everything is fine unless there's some actual evidence that something got infected.

As far as oxygen exposure, it's less risk to just pop an airlock on the primary now and leave it alone - it will be far more exposed during the racking process than it is in the fermenter right now because of the CO2 protecting it. He can certainly secondary it if he wants, but that's not necessarily going to reduce oxygen exposure. Just because the tube was exposed to the air doesn't mean the beer was exposed to oxygen - even without the CO2 blanket, surface oxygen transfer would be pretty minimal (unless he was shaking it for some reason) and just not worth worrying about.