Using the Brewers Friend yeast starter and pitching calc

[Beaner1082]

I'm a little confused about using the yeast starter calc. I need 405 billion cells for a ten gallon batch. I'm starting at 28 billion. My first starter is a 1L at 1.050 to take me up to 228 billion. I did my second starter with 1L at 1.050 too. Does that mean I just add another liter of wort to the existing starter? I only have a 2L flask to do this in.


Sent from my iPhone using Home Brew

 

[dusdau]

Just did my fourth batch, so new to this, but I had very similar question a few weeks ago, and seemed like either decanting the first wort or just leaving it in would both work. I ended up just leaving my first one in, and fermentation went great.

Given you are limited to the 2L flask, maybe just decant enough to comfortably get the second liter in??

Again, new to this, but that's my two cents anyway.

We can thankfully use the great calc at brewersfriend.com, but I found link below really helpful and interesting:

http://www.maltosefalcons.com/tech/yeast-propagation-and-maintenance-principles-and-practices

Dustin

 

[IslandLizard]

Decanting is best, it reduces the size vessel needed for the step up, while not diluting the OG of your starter wort with the starter beer from previous step.

 

[Beaner1082]

So how do you recommend I decant? Chill and let everything settle kinda like you would when washing?


Sent from my iPhone using Home Brew

 

[IslandLizard]

Yes, chill a few hours to a day, so the yeast settles to the bottom. Some yeasts do this rather quickly actually, even without a refrigerator. Then pour off the (clear) starter beer. Add the new starter wort and resume stirring. All under sanitary conditions of course.

This is not the same as washing. In washing you want to separate trub and dead yeast from the live and more viable ones. With washing you suspend the yeast in water and you harvest it from the suspension, not from the bottom precipitate, although you could.

In that light, newer yeast harvesting methods now suggest saving the entire yeast slurry, without washing. I tend to agree that there's a lot of viable yeast in the precipitated layer, and my hunch is it is also the most flocculate of the population, which is usually good to have. There's lots to read up on that.