Krausen & Blow Off

OK, my son walked me through my first oatmeal stout. Loved it! Getting ready to do another without the mistakes I made with the first. I only weigh 100 lbs and I'm gettin' old so I don't want to lift more than 3 gals. We set up a blow off but I'm not happy about how much got lost thru the tube. It may not have been that much, just unnerving. Primary was done in glass carboy & stayed there throughout the fermentation. I topped off the batch with some water after the initial blow off but sonny boy says that I shouldn't have let any of the krausen sink back in.

Questions: Do I really want the initial krausen to leave the container or can I just brew my 3 gallons in a 5 gallon carboy & let it all sink back in? Do I skim it? Do I need to top off or will that amount of empty head room be bad for it. Do I need to transfer to a secondary & top off after the initial blow off?

Your top-off should be done before you pitch the yeast. Get it up to the proper volume for the recipe, cover the top wtih a plastic bag dipped in sanitizer (at least, this is how I do it), hang on tight and slosh it around for several minutes. Then you can pitch yeast.

As for the blowoff, get a length of tubing that's long enough to go up several feet, loop around something (I use an upright for the storage rack in the laundry/brewing room), then back down into a jug on the floor with sanitizer in it. You will lose less this way. No skimming, no worries.

Cheers!

And you don't need to do a secondary if you don't want to.

Let it sink back in. It won't harm the beer and there's a lot of flavors and good stuff in that krausen. Any of the yeast gunk will settle out in the trub at the bottom of the beer once it finishes fermenting anyway, so just let it sit for a good two to three weeks in the primary untouched. I wouldn't top off any of my beers once the fermentation has begun (risk of infection). If you do partial boil batches in your brew pot, add your pre-sanitized top off water before you pitch your yeast.

If your krausening is that aggressive, consider adjusting your fermentation temperature a little lower, in the 65 deg. f. range for ales and 55 deg. f. range for lagers. You might also make a change on the strains of yeast you're using to something that works a little more slowly, and won't generate quite the same amount of krausen.

Another solution worth mentioning is the use of fermcap. It's an anti-foaming agent that is quite successful at keeping krausen to about 1" level, even in extremely active yeast on a high gravity wort. I swear by it. It's food grade and doesn't affect the taste or the color. It's also good for ending boil overs due to hot break when you're bringing your wort to boil on the stove top. A good local homebrew supply shop should have it in stock. It's not that expensive and a little goes a long way.

I like! So what about the empty head room in the 5 gal carboy? Do I need to do the primary in the bucket & transfer after the initial krausen explosion into a 3 gal carboy or is that air space bad in the 5 gal.?

There's absolutely no reason to skim it. The krausen forming and sinking back into the beer is a normal process. If you put 3 gallons into a 5 gallon carboy that should be plenty of headspace to keep it from blowing off and the extra head space will not a hurt a thing when it comes to primary. I assume the first batch was a 5 gallon batch fermented in a 5 gallon carboy? If so, that's why you lost so much to blow off because there was no head space for the krausen to expand into. Instead, it all came spewing out the blow off tube. Like mentioned before, you really don't need to do secondary. You also want to avoid topping off at this point. It will only dilute the beer and make it thinner than intended. With the proper amount of head space in primary, you should be able to let the beer ferment all the way out until it clears and then bottle it without any further action.

Thanks, I needed that! I'll do my 3 gal batch in a 5 gal carboy...and keep my back!

cyndysm said:

I like! So what about the empty head room in the 5 gal carboy? Do I need to do the primary in the bucket & transfer after the initial krausen explosion into a 3 gal carboy or is that air space bad in the 5 gal.?

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No need to transfer anything until you're ready to bottle. Unless you are doing some sort of a special step, such as adding a pound of crushed blueberries or something, there's no reason at all to rack (transfer) the beer to a secondary fermenter. The risk of autolysis (yeast die off producing off flavors) isn't really a concern for homebrewers, and I seriously doubt it manifests at all in small batches fermenting in the primary for less than a month or two.

There's no reason you can't just use buckets. I use the six gallon "better" buckets for fermenting, which you can find at homebrew shops. The only trick with them is, you need to be careful NOT TO SCRATCH the interior of the buckets with anything abrasive. Don't use anything harsher than a paper towel to clean them out, or the scratches will harbor bacteria which can infect your beer. Most homebrew shops that carry the buckets will also have sterile bucket liners, which can make cleanup a snap. Just install the liner before your brew session, and when the fermentation is all over and you've transferred your beer to a bottling bucket, just remove the liner and toss out everything (including the remaining trub at the bottom).

So, when I brew up a batch of anything, I put the wort in a sanitized bucket with a few drops of fermcap in it, seal it up and add a bubble lock, and let the whole bucket ferment in my temperature controlled converted drop freezer. I set my external temperature control towards the bottom end of what the yeast will tolerate (in it's preferred fermentation temperature range) and just forget about the bucket for two or three weeks depending on the beer. Then, i'll take some gravity readings with my hydrometer until the readings are consecutive for 2-3 days, then bottle/keg it up with a little priming sugar added to the bottling bucket.

Generally, it takes about a week to ten days at room temperatures to carbonate up, and it's usually drinkable after two weeks in the bottle unless it's a very high gravity beer, which benefits from additional conditioning before consumption.

IMHO, glass and plastic carboys are expensive, heavy and difficult to work with and clean. Scraping the trub out of a glass carboy is easier said than done if it's dried and caked in.

cyndysm said:

I topped off the batch with some water after the initial blow off but sonny boy says that I shouldn't have let any of the krausen sink back in.

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Unless you boiled/sterlized your water before topping off after the krausening, you may have infected your beer - once you pitch your yeast, LEAVE THE BEER ALONE!!

cyndysm said:

Thanks, I needed that! I'll do my 3 gal batch in a 5 gal carboy...and keep my back!

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I do 2 1/2 gallon batches in a 6 1/2 gallon plastic bucket. Very easy on my back because the bucket is so light and it has a nice handle to carry it by. If it ever slips from my hands while it has beer in it all that will happen is I will get beer all over. No trips to the emergency room from being cut by glass shards for me. Once the ferment starts the CO2 produced provides a blanket over the wort and pushes the oxygen out the airlock.

Thanks Aiptasia & everyone else! Love the idea of the removable liner and will probably do that down the road. Being new at this, I like to watch the krausen; so it's glass at the moment. Also I've been making wine for 3 yrs now so I've got 5 carboys of that bubbling away. Always fruit, no grapes for me. Can't afford it.