Pitching on top of yeast cake

Hello

Forgive me if this has been covered. But I only have time to bottle tonight and not for a brew day. However, I'd like to reuse the yeast by pitching straight onto it. If I leave the cake for a day or two then pitch on top is that going to be too long?

Actually, I searched and found a really good reply to this question here...

So, I think I'll steralize a plastic bottle pour in a bit of beer mixed cake and then put the whole thing in the fridge.

You wont need the whole cake. Get a sterilized jar and scoop some of the cake out, along with some of the beer. The yeast will settle at the bottom of the jar. When you use it, pour off the old beer on top and drain the slurry into your new beer. You will only need about 100-200 ml of slurry.

disasterjustavoided said:

Hello

Forgive me if this has been covered. But I only have time to bottle tonight and not for a brew day. However, I'd like to reuse the yeast by pitching straight onto it. If I leave the cake for a day or two then pitch on top is that going to be too long?

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You can leave the yeast cake in there. Leave a thin layer of beer on top of the cake, then put the lid back on.

I do this with every other batch. I used to transfer it to another container and wash it, until one time I had no choice to leave it in the bucket. It's so much easier and less risk of contamination to just leave it in there.

Like mass said, yoh don't need the whole yeast cake. I don't scoop any out, but that's just me.

E

Monkey55 said:

You can leave the yeast cake in there. Leave a thin layer of beer on top of the cake, then put the lid back on.

I do this with every other batch. I used to transfer it to another container and wash it, until one time I had no choice to leave it in the bucket. It's so much easier and less risk of contamination to just leave it in there.

Like mass said, yoh don't need the whole yeast cake. I don't scoop any out, but that's just me.

E

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I think that is called overpitching.

Severely overpitching...like half a gallon when you probably need less than 400ml.

I've only done it on HUGE beers so I figured a little extra wouldn't hurt. I used the entire cake from a 1.065 pale ale for a 1.108 imperial stout.

One thing I heard when researching is that it is sometimes a bad idea to reuse yeast (more than a few times, anyway). Your beer environment at the end of fermentation is not the healthiest place for yeast. Basically, if you do a couple strong beers in a row you force a survival of the fittest situation and only the most alcohol-tolerant yeast will remain. Which is fine if you have a very strong and flavorful beer. But if you are making a less complex beer after something monstrous, you may lose the best flavor-providing yeast and be left with only the most alcohol-tolerant yeast.

Basically, you shouldn't reuse too many times and you should make a stronger, more flavorful beer each time.

My two cents.

You are not singling out the strongest yeast. At 12% abv the yeast are still alive, just not healthy. You don't want to force stressed yeast to reproduce because you will not get good results. Something else to consider is that the more yeast multiply, the more flavor you get. If you severely underpitch, there is a huge amount of reproduction, so huge amounts of esters. Conversely, if the yeast do not have to reproduce at all or maybe only once due to a huge pitch, you end up with very little flavor.

This may seem counter intuitive, but while increasing pitching rate decreases esters, it increases fusel alcohols. If you keep the temp down, it might not be much, but if the temp is on the warm side and OG is high, you may be in for headache beer. High temp, high pitching rate, and poor yeast health all will increase fusel alcohols.

*Edit* Some sources say increased pitching rate lowers fusel alcohol production while others say it increases it.

I've pitched on the cake a couple of times- once for a light lager, when I went up to a big dopplebock, and once for an Arrogant Bastard clone when I started with a smaller pale ale.

Here's some great information about the negatives to this, from a brewery consultant: https://www.homebrewtalk.com/f163/why-not-pitch-your-yeast-cake-166221/

That's what I like about this forum, one question and so much applied knowledge comes back. Cheers folks. Actually, I do now have two bottles fo yeast cake in my fridge. I'm aiming to go from an English Mild to a lightly smoked Porter. So should be ok.

So yeast inbreeding is OK...sometimes.

Pitching on the yeast cake is a massive overpitch. I've done it a couple times and didn't like the result, but to each their own. Harvesting and repitching a portion of the yeast cake I am a huge fan of.