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-   -   New Starter, then washing question (http://www.homebrewtalk.com/f163/new-starter-then-washing-question-372168/)

Grannyknot 12-05-2012 06:57 PM

New Starter, then washing question
 
This weekend, I plan on doing a beer that will be between 1.070 & 1.078 (don't quite have my efficiencies dialed in yet). So Thursday night, I plan on doing a 1.5L yeast starter with wyeast 1450, with 5.5oz of DME & intermittent shaking, decant that wort friday, and then add 1.5 more liters of wort with 5.5oz DME.

My calculation shows that my yeast starter will have around 325 billion cells by saturday afternoon, of which 280 will be needed for the upper range of my original gravity (1.078).

So thats the first step. If i've done anything wrong, thus far, please let me know.

Next, I had planned on washing this yeast after about 2 weeks in the primary. Yesterday I noticed on HBT that one guy said he never washes any yeast that has been working on wort at or above 1.070 because it is overworked and unhealthy. Is this an accurate statement? If this is somewhat accurate, is it still ok to wash this yeast, since I have overpitched by 50 billion or so cells? Should I overpitch by even more, like 100 billion cells?

One final question. Once this yeast is washed, is there any way to get an accurate estimate of viable cell count? Or should I stick to smaller beers with my washed yeast starters?

WoodlandBrew 12-05-2012 08:32 PM

You don't need to increase your pitch rate unless you are trying to reduce the flavor component of the yeast or lagering.

Viability off a fresh cake can range from 60% to 97% IME. The best way to tell is with a cell count. I don't have enough data to say what the variation in viability is, so I can't say what higher gravity will do.

It seems like the thing to do these days is to save 100 billion cells from your starter instead of saving the cake. Then you can use that just like a vial or pack of yeast for another brew.

Here's how I do my cell counts:
http://woodlandbrew.blogspot.com/2012/11/counting-yeast-cells-to-asses-viability.html

Grannyknot 12-05-2012 09:01 PM

Ok, apparently your answer was quite a ways over my head.
Lets just throw out the whole counting yeast cells question.

Are you saying I don't need to do a 2 step starter in the first place? How would I get the 280 billion required yeast cells?
And is there any truth to the theory that washing yeast from a high gravity beer isn't good?

Jayhem 12-05-2012 09:07 PM

I've only been washing yeast for about a year but it seems that when I do a 2L starter for my 11 gallon batches it creates about 1-1.25 cups of white yeast cells once it finishes. I decant the liquid and pitch 1/2 - 2/3 cup of thick yeast slurry to each 5.5 gallon batch and this has always been a perfect amount of yeast...I have krausen within 12 hours and heavy activity within 24 hours...beer tastes great.

I am not concerned enough with it to go through all these fancy cell count calculations because without lab testing you really do not know your viability % anyway.

Grannyknot 12-05-2012 09:12 PM

Quote:

Originally Posted by Jayhem (Post 4653093)
I've only been washing yeast for about a year but it seems that when I do a 2L starter for my 11 gallon batches it creates about 1-1.25 cups of white yeast cells once it finishes. I decant the liquid and pitch 1/2 - 2/3 cup of thick yeast slurry to each 5.5 gallon batch and this has always been a perfect amount of yeast...I have krausen within 12 hours and heavy activity within 24 hours...beer tastes great.

I am not concerned enough with it to go through all these fancy cell count calculations because without lab testing you really do not know your viability % anyway.

hmm.....I have to say its somewhat refreshing to find someone that doesn't necessarily use the yeast calculators. Interesting that you just eyeball your pitch measurement and save the rest. Curious to hear what others think about this.

Bamsdealer 12-05-2012 11:11 PM

I obsessed over this stuff at first too. After the first starter has been chewed up, just chill, decant and add more dme, let ferment, chill, decant and pitch. It really is that simple. Even a fresh vial of yeast in a 1.5 L starter would likely do fine in your beer.

Now, ifI want to brew something that requires stepping up, I just brew something under 7% abv and save the yeast in a mason jar for the next batch. The same yeast calculators can be applied to fermenting a full batch.

For example, If say 800 billion yeast cells are produced in a 5 gallon batch, just eyeball a 1/3 of the slurry for a brew that requires a cell count in the 250-300 billion range.

WoodlandBrew 12-06-2012 12:46 AM

Even if you are within a factor of 5 it will probably be fine. A factor of ten is where I have started to notice a difference. The number of cells viable cells generated by fermentation can vary quite a bit. In a slurry can 1 trillion to 4 trillion seems pretty normal for the 3-4 gallon batches I do.


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