Re-using Trub At Bottom Of Fermenter?

[crusher]

Hey Fellas'
Back on re using trub from fermenter,is it possible to get a brew going from pitching on top of trub left at bottom of secondary. Reason I'm asking is I was wanting to put on a brew tomorrow & completely forgot about getting a starter going beforehand. I have a APA coming out of secondary & if possible will dump on top. Thanks for any help.
Crusher.

 

[Steve]

Crusher
Yes...ive heard of lots of people doing it with no worries. Obviously as long as your new brew is similar to the APA that is done.
Cheers
Steve

 

[homebrewworld.com]

Oh yeah, i works like a train !
Dump onto the previous yeast cake, and whoooshka!
I agree with AlienBoy, i wouldn't do it straight onto the cake more than once or stretch it to twice.
go for it !
cheers

 

[crusher]

Fellas,thanks for response. I have dumped on top of primary before no problems, but what I was wondering was can you do it on trub left at bottom of secondary
Crusher.

 

[nonicman]

Hi Crusher,
I've not pitched onto the yeast that has dropped out in secondary. I would assume that this yeast are the strugglers in the yeast population (as I'm guessing you are thinking the same), but they are alive (you could test them in a starter), and hopefully willing to work. If you have no other option, they could get you started untill you can get some fresh yeast or a packet of dried yeast.

I would go for it but would be worried that the yeast will not fully ferment the wort and hence I'd get some fresh yeast ASAP, however it may work fine and would be better than not brewing.

Hopefully POL or someone knowledgible can set you straight.

edit: sp

Edit: from the following posts it appears my above concerns are not fully justified.

 

[Trent]

Crusher
I have pitched onto a primary cake before, and it ended up tasting awful. I am pretty sure, and anyone may feel free to correct me, that the reason we rack to secondary is to get the beer off the primary cake, which will contain alot of dead/dying cells, which COULD lead to autolysis, which is what appeared (I assume) to happen in my experience, cause it was in summer and I didnt have a ferment fridge then. The yeast that makes it through th secondary is still in suspension, and eating away the sugar, and should be more than healthy enough to kickstart again in your new brew. I am about to do this with a russian imperial stout, and Darren pointed out to me that if the OG of your original beer was more than 1055, they yeast may not be in the best shape, and it could benifit from dropping in a few litres of about 1030 wort for a few days to bring em back to life, the drain that off and pitch your new brew. I know that Palmer also recommends dropping big beers onto a secondary yeast cake, not a primary cake. So, I reckon the only way to go is onto a secondary cake (IMO), and I dont think that you will need to add more yeast, just make sure ya aerate well.
All the best
Trent

 

[sosman]

Fellas,thanks for response. I have dumped on top of primary before no problems, but what I was wondering was can you do it on trub left at bottom of secondary

[post="63216"][/post]​

Crusher, I haven't done this personally but from all accounts that works just fine. Remember that yeast that made it to secondary is likely to be less flocculant than the stuff glued to the bottom of the primary. Recycling this multiple times might lead to flocculation problems among other things.

On the plus side, the yeast should be fairly clean and relative free from hop residue and break material.

 

[nonicman]

8.1.1 Yeast Factors

The first step to achieving a good fermentation is to pitch enough yeast. The yeast can be grown via yeast starters or it can be harvested from previous fermentations. When yeast is harvested from a previous fermentation, it should be taken from the primary yeast cake and preferably from the upper layer of the cake or from the secondary. This yeast will have the optimum characteristics for re-pitching. In either case, you should target pitching at least 1/3 cup (75 ml) of yeast slurry to a typical 5 gallon batch of ale or 2/3 cup of slurry for lagers. For stronger beers, OG > 1.050, more yeast should be pitched to ensure optimum fermentations. For very strong beers like doppelbocks and barleywines, at least 1 cup of slurry should be pitched.

http://www.howtobrew.com/section1/chapter8-1-1.html

Well there you go, secondary yeast may be ok after all.
Trent, I've not had any problems with fresh primary slurry, however, generally use a fresh fermenter and don't add all the slurry (including trying not to use the thick bottom layer left in the primary fermenter), and have a converted freezer to regulate the high temps produced by using a large yeast population.

 

[Bilph]

I've pitched straight onto the secondary. It works fine, but there is a lot of yeast in yeast cakes, even in the secondary.
You only need about half a cup of slurry.
I would actually suggest just rinsing the secondary with cooled boiled water.
Wash it through into a sterilsed container and let the heavier stuff settle for a bit (even 10mins or so) and pitch the yeast suspended in the liquid into your next brew.

 

[Trent]

Nonic
The time I pitched onto the primary cake, I just poured my next brew on top of the whole cake, as per instructions from a HBS guy. As we all know, those instructions arent always accurate, so maybe had I have done it the way you did it, I may not have had the problem I did. After reading Chillers yeast farming article (excellent article BTW), and reading Bliph's post, I may just even try it for my RIS, cause it sounds pretty sensible.
All the best
Trent

 

[Weizguy]

I agree with Trent re the possibility of autolysis. It may take a bit longer to happen in Winter, but still can occur. However, it should not occur if you rack and bottle on the regular timetable.

Do not leave the beer too long on the yeast cake. There are already big numbers of fungi in the there (yeast, that is), and some are probably turning to the dark side already. Yep they are thinking about cannibalism (teliologically speaking).

The batch should take off like a rocket and ferment quickly, so monitor the gravity and rack at the relevant time. This should leave most of the old burnt-out cells behind.

It just goes to show how well a ferment can occur when pitched with appropriate yeast density.
Beers

Seth out

 

[vlbaby]

I have to wonder how critical the timing is in regard to autolysis. I would imagine that seeing coopers and many others bottle condition their beers, then the yeast must last a long time before they die and rupture bad flavours into the beer.
But I could be wrong, its happened before.


vlbaby.

 

[Weizguy]

I have to wonder how critical the timing is in regard to autolysis. I would imagine that seeing coopers and many others bottle condition their beers, then the yeast must last a long time before they die and rupture bad flavours into the beer.
But I could be wrong, its happened before.


vlbaby.

[post="63388"][/post]​

vl,

I think that the yeast numbers are the problem. As U might expect, the bottle-conditioned beers have only a thin layer of yeast and a small amount of yeast.

However, in the bottom of the fermentor, there exist a large population of yeast cells and the pressure (both physical and envrironmental) on each cell is heavily increased.
They have to cope in a milieu of yeast waste products and trying to exist close to expired cells etc. A vague analogy to the New York or Hong Kong environments could be drawn.

Seth