Another question on reusing yeast...

[seanmac]

Hey guys, I know there s so much out there about washing and reusing yeast etc, but there is just far too much conflicting information that you read and well it makes my head hurt. I guess yeast is just too amazing.

Anyway, this is my situation.
I brewed a beer last Thursday(doing AG, but that dosnt make a diff), and It will be finished fermenting around now, maybe in the next day or two. I was gonna put another brew on later today and to save on a whole packet of yeast, I was wondering what is the best way to reclaim the yeast from that brew.

I read the other day that simply the case of scimming the krausen off the top of the beer(it look beautiful atm), and using that in my new brew will produce a great fermentation, is this correct as this sounds the easiest way?

The other option seems to be to rack the beer and then to brew directly on top of the trub at the bottom. I know this then brings up lots of other questions about sanity etc, but again everyone has different views!

So basically, am I correct that if I take my krausen and add it to my new brew, it will ferment?

Cheers for the help guys!!

 

[Brycey]

I think top cropping needs to be done after the first two or three days !

I have just saved the trub from my ag wheat beer, i left some of the beer at the bottom gave it a mix and split it into two sterilised 2l pet bottles and put them in the fridge, hope to use these for my next couple of brews.

Cheers
B

 

[LeithR]

seanmac,
Both approaches are worth doing skimming the Krausen is supposed to recover good healthy yeast altho you don't get too much of it. Using this approach you will need to grow on your yeast for the next brew in a 2L bottle in the airing cupboardfor a few days. There is a good how to on here detailing how to do that. If you elect to use the yeast cake after racking off a previous brew I strongly recommend that you take the yeast cake and a little of the previous brew out of the FV into a bottle and then sanitize the FV before putting your new brew into it, you can then add back the yeast cake into the brew.

I also keep recovered yeast in the fridge for a few weeks before using again but always make up a starter to ensure that the yeast is in good health before pitching it into a new brew. This way you can keep good track of what the yeast has been used for previously and what type/make of yeast it is.

 

[mike77]

I reckon that if it is finished fermenting then the krausen will have dropped already so it is too late to skim it.

This is probably not best practice but I would.

1) Rack the beer
2) Save a cup full of slurry in a serialized cup and cover it
3) clean the fermenter
4) brew the new beer then pitch the saved cup of slurry

 

[nixhaz]

Just to show what a heathen I am, I now regularly pitch onto the yeast cake, and it's awesome (so far!!). I only do it once, so only 2 generations of yeast. Only once have I pitched onto a 2nd generation cake so I chucked half of it away first, but it still tastes fantastic, just brewed a bit quicker. No off flavours, whatsoever. Works for me, but ymmv :)

I never open the FV, so it only risks getting infected when I rack the beer off the lees, and then I immediately throw the new wort on top. I always taste the original beer to make sure it isn't wonky, and always have a pack of yeast on hand in case it has gone wrong!

 

[seanmac]

Cheers for all your help guys.

I just finished brewing it now and hoping to hear some bubbles soon!!

In the end I done exactly what most of you suggested by racking my beer, transferring the 'yeast cake' into a new clean FV, and then putting my new freshly brewed batch on top of this yeast. Will be quite interesting to see if this gives the beer any different flavour than just using yeast, also it saves that whole couple of quid on a sachet of Safale.

Thanks again for the comments!! Now I just need to start drinking that previous batch so I have bottles once fermentation is finished.....