Re-pitching w/ trub from primary

dirtymartini said:

Could someone give this newbie a good explanation of what a yeast cake is? Is it just the trub on the bottom of the primary fermenter? Why is it called a cake? Inquiring (Noob) minds want to know!!

BTW I found this thread using the search.

Click to expand...

Yep, the trub on the bottom. Why it's called a yeast cake I could imagine comes from what it kinda looks like. Princeton definition:

small cake of compressed moist yeast

i have a stout in my primary that is a plastic bucket. i am going to rack it to my carboy in a week at which time i was planning on pouring a porter onto the cake in the plastic primary. how would i make a blow off tube for a plastic bucket?

Wanted to keep this thread going. I found this through the search as well. I have a stout in primary right now (though I'm afraid it's more of a porter) and am planning to try my hand at an oatmeal stout as my first partial mash. Good thing I read this thread, too because I would've just used an airlock on my 6.5 gal. bucket thinking it was enough. Apparently not!

A blow-off would be nothing more than just the size stopper I already use fitted with a tube that leads to a bucket with water in it right?

Madvillain said:

A blow-off would be nothing more than just the size stopper I already use fitted with a tube that leads to a bucket with water in it right?

Click to expand...

Pretty much. I only did a blow-off with a bucket once. And that was after the top blew off like a shot-gun in the early morning. Beer everywhere! But, it's not always going to ferment that wildly but you probably have an 80% chance.

Anyways, what I did was pretty much what you stated. Take a hose and put it around the center of your airlock (no water in the airlock naturally) and the hose goes to a bucket with some sanitizer in it. The only thing I did though was cut off a bit of the tip of the airlock that goes into the bucket. You need enough room for it to flow out / not get clogged. No guarantee but if it gets blocked up; BOOM and its time to clean up. Ultimately a carboy is better suited but enough people here rig something up with a bucket. FYI my top put a dent in the ceiling...

desertBrew - Thanks for the tip, wow I can't imagine an explosion of that magnitude. I'm actually kind of scared about it because I'm keeping my primary in a storage closet ( I live with my GF at her parent's house) and if it blows it will spew all over her father's golf stuff which would not be good (obviously). Maybe I will save this for another day when I have my own place!

I'm thinking of trying this for the first time with my next batch - I've got a great fermentation going now that I'd like to replicate. My question is about adding the new wort to the cake. I dont get a full boil, only about 3g. Would you add the wort then the topoff? water first? mix in another bucket then add it all at once ?

and then there's a differance of opinion...

i have always had an aversion to repitching into a dirty carboy. something about it just doesn't seem right.

i do collect the slurry and let it settle out and store it for the next batch

After siphoning from the primary into secondary, I dumped the thick yeast cake into a sanitized 12oz bottle and sealed. There's a couple inches of liquid and the rest is yeast cake. How long will this store in the fridge? I want to use it as a starter for my next batch. I'm sure it is under a little pressure. Will this help or hurt the yeast?