I don't understand yeast cakes, and reusing them.

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natewv

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So I just brewed a batch last night and now the clock is ticking for planning my next batch. When I rack to secondary, I just leave the yeast cake and reuse it? I read the thread about washing my yeast

https://www.homebrewtalk.com/f163/yeast-washing-illustrated-41768/

but I still don't understand. So when I rack this Blonde Rye to secondary in a few weeks, I usually leave some amount of beer on the yeast cake obsviously so as not to add the trub to the secondary. Can I just throw a new batch of wort right on top of it? Do I need to go through that washing process? What would happen if I do not?

I have a Burning River Pale Ale clone from AHS that uses the same strain of yeast as the Blonde Rye that's fermenting now.

Also I read in a few places about Hard cider and i was maybe thinking of using the yeast cake for that?
 
Sure, you could rack from your chilled wort right onto the yeast cake to reuse the yeast. Just give it a good brisk stir to resuspend the yeast.

The only reason you wouldn't want to do this is if the style of beer you were making called for a different strain of yeast, but you state that they both use the same, so you are good, reuse those yeast!

Oh, but you don't want to just leave the yeast cake sitting in the unused buckets for more than a couple of hours. If you want to use it a few days later, you really need to put it in a sanitized container and keep it in the fridge.

If you do this, note that only the top WHITE layer of the yeast cake is actually yeast. The rest is trub. You want to try your best to just harvest the white yeast and disregard the trub. This will lead to happier, healthier yeast.

Keep reading up on harvesting and washing yeast.

If you are going to rack directly onto the yeast cake immediately after you moved the other beer to secondary, that is OK too. The trub part of the cake will just settle back with the trub from the new beer, so no real harm.

Also remember that dry yeast cost about $.50 at your LHBS as well, so no big whoop if you can swing by and get some more.
 
When reusing the cake, you want to go from lighter, less hopped/spiced/whatever beers to darker, more hopped/spiced/whatever beers. The blond Rye to a Burning river clone should be fine. Just don't pitch a bud light clone onto a stout cake for example without washing the yeast.
 
You can go from same style to same style thought correct? I am doing a beer right now where the yeast cost about 40$ but the ingredients where about 16 so I am going to make 3 batches of the exact same beer and then switch to a slightly darker style.
 
The down-sides to pouring your next beer right onto an old yeast cake are:
1) you are most likely over-pitching (using too much yeast). The yeast grew and multiplied to handle the sugars in your last batch of beer. That growth and reproduction process imparted a flavor to the beer (usually the estery/phenolic profile). If you over-pitch, then the growth doesn't happen which will result in the beer tasting different (regardless of it being the same recipe or not).
2) the trub from the last beer may impart a flavor on your current beer. It probably won't be detrimental, but it may not result in the flavor you were shooting for (unless it is the same beer multiple times - like you mentioned).

Although you --can-- rack right onto the last cake, it's probably not the best choice unless you are okay with the assumed consequences. I would recommend washing and pitching the correct amount (I use the Mr/ Malty Calculator) to make the best beer.

Lastly, it is advised to go from smaller/less complex to bigger/more complex beers, but you'll be perfectly fine pitching into the same beer multiple times.
 
Thank you for the advice guys. So, to wash my yeast...I found a post from 2007 I copied below...is it missing anything? So essentially washing yeast is just adding some boiled water and then taking off the top a couple of times? Say I do this, is this amount of yeast what I should use for my next batch?

Also, if you wash yeast, is the rule of thumb to go from lighter to darker/more flavor still in play, or do I then essentially have fresh (in this case) Wlabs English Ale yeast?

Not really. Washing yeast is actually quite easy. I have two, two quart apple juice bottles. Obviously, sanitize the crap out of them before use. Then, after you rack your beer, take about a quart of boiled and cooled water and mix it up with the trub...then pout it all into the bottle (you may want to have an extra sanitized jar laying around as sometimes it wont all fit in one bottle), then let it settle for a couple of hours, agitating it every so often, to keep the yeast in suspension while allowing the heavier stuff to settle. Then carefully transfer the liquid on top to the second bottle. Again, agitating occcasionally and allowing the heavier stuff to fall out. In the meantime, clean and sanitize the first bottle. Then after an hour or two, dump the liquid from the second bottle, back into the first bottle and chill. When the liquid chills, the yeast will fall out of suspension and collect on the bottom of the bottle. Dump off the majority of the liquid, and add your yeast to a sanitized jar and label. I know it sounds like a lot, but it really is not.
 
The down-sides to pouring your next beer right onto an old yeast cake are:
1) you are most likely over-pitching (using too much yeast). The yeast grew and multiplied to handle the sugars in your last batch of beer. That growth and reproduction process imparted a flavor to the beer (usually the estery/phenolic profile). If you over-pitch, then the growth doesn't happen which will result in the beer tasting different (regardless of it being the same recipe or not).
2) the trub from the last beer may impart a flavor on your current beer. It probably won't be detrimental, but it may not result in the flavor you were shooting for (unless it is the same beer multiple times - like you mentioned).

Although you --can-- rack right onto the last cake, it's probably not the best choice unless you are okay with the assumed consequences. I would recommend washing and pitching the correct amount (I use the Mr/ Malty Calculator) to make the best beer.

Lastly, it is advised to go from smaller/less complex to bigger/more complex beers, but you'll be perfectly fine pitching into the same beer multiple times.

Yes. And, from Mr. Malty:

"If (and that is a big 'if') you've got excellent sanitation all the way through the process and have provided proper yeast nutrition (including O2), you have a gold mine of healthy yeast ready to reuse. Of course, you don't want to reuse the whole thing. I know a number of people dump a new batch on top of the yeast cake, but you're not going to get the best beer that way. Yeast do need some growth to result in the right kind of ester profile, etc. While too big a pitch is better than too little, it is pretty easy to figure out how much you need and pitch just that."
It is advised not to repitch on an entire yeast cake, but instead, harvest some healthy cells and pitch properly.
 
Does this also grab bacteria? I am hesitant to do this because I am mixing 2 yeasts and lacto. Also this experiment could be expensive for me, so how not worth it is it to re-pitch the same beer on the same yeast cake? If it grabs the lacto as well, this sounds like an option for me.
 
go on youtube and look at some videos. The thread that always get tossed around on here is good, but I didn't really feel comfortable with the process until I watched people do it on youtube.
 
When reusing the cake, you want to go from lighter, less hopped/spiced/whatever beers to darker, more hopped/spiced/whatever beers. The blond Rye to a Burning river clone should be fine. Just don't pitch a bud light clone onto a stout cake for example without washing the yeast.

I've pitched from dubbels to Belgian blondes, stouts to pale ales, and a Munich dunkel style ale to a Kolsch without washing and no observable color bleed-over. Rack well and it won't be an issue.
 
What I don't understand is why my yeast look like it has 4 layers? What am I doing wrong?

Top = Beer/water
Next = Yeast
Below that = Trub
Bottom = More yeast?

This is the same jar just different exposure

I have never seen only 3 layers in my 3 washings so far, it always looks like this so I don't pour off anything

IMG_5289_small_1.jpg
IMG_5291_small_1.jpg


Thanks in advance
Toy4Rick
 
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