[paul]

New to all grain, five batches now with washed yeast, all IPA's and same grain bill, the beer's pretty good, how far can I push it.

[swampale]

I have heard at least 12 times. I have never gone that far yet since I constantly brew different styles of beer.

[majorvices]

New to all grain, five batches now with washed yeast, all IPA's and same grain bill, the beer's pretty good, how far can I push it.

Over 20 years of brewing (including 6 years pro) and I have never bothered to wash yeast. But if you are doing a lot of heavily hopped beers I can see potential benefit to remove hop resin from cells. However, you will probably be encouraging mutation because of the stress you are putting on the yeast. So I'd be wary of going much more than 5-7 gens.

Personally also feel you could probably go that m any gens easily with unwashed yeast.

[ynotbrusum]

The most that I have gone was somewhere around 25 repitches, but it was unwashed Pilsner yeast that was given yeast nutrient at each repitch.  I basically used it for a couple years and simply grew tired of the project.  I never had an off beer. YMMV, of course. 

Also, I have had petite mutants form in just a few batches when repitching, so it does happen, if the yeast is stressed.  I rarely go beyond 5-6 generations anymore, because yeast is just not that expensive to risk large batches betting on its unaltered replication with straight repitching.  Guys who yeast farm typically save some first generation yeasts to propigate from, I think.

[Big Monk]

A little care taken in trub removal processes can do wonders for the harvested yeast. The clearer the beer that goes into the kettle, then into the fermenter, typically (YMMV) yields a purer mass of yeast for harvesting.

[denny]

First, unless you're acid washing the yeast, you're rinsing it, not washing it.  Like Keith I have found no value in doing that.  Most of the breweries I work with don't do it either.

[tommymorris]

I think we are maybe getting too technical.

What a lot of people do is grab a portion of the slurry on the bottom of the fermenter and use that for the next batch. You can use the slurry calculator on Mr. Malty to estimate how much slurry you need.

You can store slurry under the beer it came from in a clean and sanitized jar.

This is a lot easier than doing the water rinsing techniques (aka washing) and just as effective. In fact, many knowledgeable yeast experts say just keeping the slurry is better.

I never repitch more than 3 times but that is because I usually want to move on to a new yeast by then. I have found slurries only last a month or two before they start to discolor. I toss them at that point.

[HoosierBrew]

I think we are maybe getting too technical.

What a lot of people do is grab a portion of the slurry on the bottom of the fermenter and use that for the next batch. You can use the slurry calculator on Mr. Malty to estimate how much slurry you need.

You can store slurry under the beer it came from in a clean and sanitized jar.

This is a lot easier than doing the water rinsing techniques (aka washing) and just as effective. In fact, many knowledgeable yeast experts say just keeping the slurry is better.

I never repitch more than 3 times but that is because I usually want to move on to a new yeast by then. I have found slurries only last a month or two before they start to discolor. I toss them at that point.

Yep. I repitch slurry on occasion, but just never bought in to the yeast washing thing. And IIRC Mark V was pretty adamantly against the practice.

[majorvices]

I was assuming acid washing.

[Delo]

Acid washing was big, but short lived in the 80s. Now the trend is unwashed.  I  hear acid washing may make a comeback.


on a serious note, I also just use some slurry. I did the rinsing thing a few times and didnt really find it any better. I brew using a variety of yeasts so the most I have done was 3.

[AnimalChin]

Is trub and slurry the same thing? I thought slurry was "clean/washed yeast" and that a yeast cake was the same as trub which is all the "junk" at the bottom of a fermenter after fermentation is completed. I'm re-reading what I just wrote and it sounds so anal but I feel like if I use something like Mrmalty, I need to know if the amount of "stuff" that I'm estimating my billions of cells count is from dirty trub or clean/washed yeast.

If I have 150mL of trub vs. 150mL of washed yeast, my viable cell count will be very different.
Anyway, just trying to get my definitions straight before I go and over/under pitch. 

[denny]

Is trub and slurry the same thing? I thought slurry was "clean/washed yeast" and that a yeast cake was the same as trub which is all the "junk" at the bottom of a fermenter after fermentation is completed. I'm re-reading what I just wrote and it sounds so anal but I feel like if I use something like Mrmalty, I need to know if the amount of "stuff" that I'm estimating my billions of cells count is from dirty trub or clean/washed yeast.

If I have 150mL of trub vs. 150mL of washed yeast, my viable cell count will be very different.
Anyway, just trying to get my definitions straight before I go and over/under pitch. 

It just doesn't make that much difference.  When a batch is done with primary, I pour the slurry/trub into 2-3 sanitized containers.  The next time I brew I pull one out of the fridge and pour it in.  That's all there is to it.  Yes, I used to do the whole nine yards.. rinsing, using yeast calculators, etc.  But you know what?  My beer was no better for doing that.  Being pragmatic, I decided to try the easy way and never went back.

[AnimalChin]

It just doesn't make that much difference.  When a batch is done with primary, I pour the slurry/trub into 2-3 sanitized containers.  The next time I brew I pull one out of the fridge and pour it in.  That's all there is to it.  Yes, I used to do the whole nine yards.. rinsing, using yeast calculators, etc.  But you know what?  My beer was no better for doing that.  Being pragmatic, I decided to try the easy way and never went back.

Thanks for the response Denny! I've been hearing what you wrote from a lot of people. I was thinking I'd hear the opposite. 

[biestet]

Is trub and slurry the same thing? I thought slurry was "clean/washed yeast" and that a yeast cake was the same as trub which is all the "junk" at the bottom of a fermenter after fermentation is completed. I'm re-reading what I just wrote and it sounds so anal but I feel like if I use something like Mrmalty, I need to know if the amount of "stuff" that I'm estimating my billions of cells count is from dirty trub or clean/washed yeast.

If I have 150mL of trub vs. 150mL of washed yeast, my viable cell count will be very different.
Anyway, just trying to get my definitions straight before I go and over/under pitch. 

It just doesn't make that much difference.  When a batch is done with primary, I pour the slurry/trub into 2-3 sanitized containers.  The next time I brew I pull one out of the fridge and pour it in.  That's all there is to it.  Yes, I used to do the whole nine yards.. rinsing, using yeast calculators, etc.  But you know what?  My beer was no better for doing that.  Being pragmatic, I decided to try the easy way and never went back.

This. I've even stopped following the convention of light to dark, lightly hopped to heavy. If you follow good clean brewing practices, yeast will be good to use again by just collecting it in a clean container.

[bbt95762]

@Denny, when you save and re-pitch the trub, are you saving in pint? or quart jars? (and what size batch?)

I do 5 gallon batches.  I've cleaned/saved/re-vitalized and re-pitched yeast...sure would be a lot nicer to just re-pitch some trub.