back to back batches

[axis714]

Im just curious to know some techniques on re-pitching a good yeast from one batch to the next.
Ive read posts on here about saving a little $ running back to back batches and im not sure how i should do it. Ive always pitched fresh yeast with every brew.
Do I salvage the trub from the primary? secondary? or save a sample and condition with extra dme at bottling? and how many times would this be considered a safe practice w/o fear of bacterial contamination?
If my thinking is right as long as ive got the process going full tilt i could theoretically produce the same beer back to back for like 3 batch runs, correct?

[mmmBeer...]

I have yet to try this, but a lot of people here just pour the new wort right on the yeast cake out of primary after raking the beer to secondary. I can’t seem to time things that well (what with a 2.5 year old and all), so I tend to wash the yeast out of primary and store it in the fridge for the next batch. Others split the starter several times and pitch fresh on each batch.

As fro number of batches you can reuse the yeast for I think it was not recommended in another thread by brewmonkey that you don’t go past 6 batches (anyone can feel free to correct me on this).

[paul84043]

Another consideration would be to use hop bags when boiling your wort to minimize the amount of Extra stuff you leave behind in the primary for the extended period of time.

I am considering doing a couple of batches like this, from what I hear, they really take off and ferment like hell....

[axis714]

Thats why i was asking for ideas ....i have in mind to make approx 15-25 gals. of the same porter and i think itll be really great if the same yeast is kind of cultivated throughout the entire 3-5 batches just to see the ferment activity and how well it takes off....thx for the suggestions, i think ill try just pouring over yeast cake in primary seems simple enuff. maybe save a little starter back just incase.

[Beerconnoisseur]

...was mentioned earlier, (I believe by toneyc, and others) where you make several parallel starters from the same yeast sample, before you brew with it. Then, you just add each starter to each batch. This has the benefit of reducing off-flavor transfer from one batch to the next, but you also may lose any interesting flavors that occur in one batch, but not in others.

[chris1kanobi]

Here is what I do: I brew a beer made with a 1000ml starter. Then when I rack that beer, I save the primary yeast cake in a sanitized flask or jar with an air lock on it. The yeast will settle to the bottom and a layer of beer will rise and cover the yeast. I leave it at room temperature untill I am ready to brew again. Usually within 2 weeks. A bit of autolisis will take place, and the yeast flavor will change a little bit, the more you reuse and the longer you wait to use it. I only reuse the same cake 3 times, before starting again. I don't keep the cakes for long periods of time due to the risk of mutations and contamination. I airate the wort very well and pour the entire flask into the second brew. Often there is airlock activity in 10 min. or less. I use pellet hops, and I don't bag them, so the trub is often thick and chunky. I have never noticed any hop influence from a previous batch. I have even reused a cake from an IPA to brew a Stout and the bitterness, flavor or aroma from the previous batch was not detected. You can always pour a bit of the beer off the top of the yeast cake and taste it for potential contamination.

[axis714]

although this is not "the wine forum" i just thought id post that i recently tried this line of thought in a 1 gallon jug of wine im making....i racked it topped up and poured fresh juice over the yeast cake and 6 hrs later im watching a full ferment krausen arise....hopefully this is the same effect ill get from my brew next time around thx alot guys i now know how to make that 5$ wyeast last a bit longer for me..im all excited to try this method w/ 20-25 gals...seems like the way to go for quantity brew.

[brewmonkey]

http://www.realbeer.com/discussions/showthread.php?s=&threadid=1421&highlight=repitching+yeast

[sallad]

i talked to a guy at my LHBS who dumped his wort on the previous yeast cake, and that night his glass primary exploded. so, be careful- there is lots of very active yeast there!