first yeast starter. this doesn't look like enough

This is English ale yeast WLP 002. I used 10/1 ratio DME to water boiled and cooled. The stir plate worked flawlessly and I covered it with foil and let it go three days and this was the end result. It seems like far too little. Does this strain of yeast not reproduce as much as others or was I just expecting too much. I would estimate that there's about 3 or 4 times as much yeast as was in the original vial. I guess I thought I would have at least a ten fold increase.

zoomzilla said:

I used 10/1 ratio DME to water boiled and cooled.

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What were the units here? Common practice is generally the the opposite of what you said, where you have a 10 / 1 ratio of water in milliliters to DME in grams. That is, common practice would have 2000 ml water to 200 g of DME, resulting in a starter wort OG of something like 1.036. In that case, assuming you had a rather fresh vial (e.g. 90% viability), then the Braukaiser model for yeast propagation on a stipulate would predict approximately a 4-fold increase (e.g. from 90 billion cells to 370 billion cells).

Calculator for this is here: http://www.brewersfriend.com/yeast-pitch-rate-and-starter-calculator/

That has links to the yeast propagation model Kai uses.

Assuming the wort ratio was right that looks like a very healthy amount to me.

Is that a 1-quart mason jar? If so, looks like around 450 mL. At 1.040 SG, you would go from 100 to around 150-200 billion cells based on the Brewer's Friend starter calculator. If its a 2-quart mason jar, looks like 900 mL, which would yield around 250 billion cells. So either way, you would expect between 1.5-2.5 times the original yeast count. Not sure why you expect ten times growth.

Starter Calculator

I think it's safe to assume he meant 10/1 water to DME, as the opposite would be pretty thick. To me, that looks like a healthy amount of yeast, but that's just a guess since I don't know the batch size, starting gravity, and the actual starter size.

Also, starters won't grow the yeast tenfold. I think the number is something like a 150% to 200% increase, but I can't remember exactly. Check out http://www.woodlandbrew.com/ there's a lot of great research and information regarding yeast growth and starters.

OK great, thanks for the info. I have no basis for expecting such an increase. Just thought it would yield more but this seems right in line with a normal starter. And sorry for messing up the ratio.

That looks good to me. It also looks like you recently pulled it off the plate because the starter beer is still murky. Put that in a relatively cool place for a few hours and the liquid will be super clear. That will mean that much of the yeast currently in suspension will have dropped to your yeast cake on the jar's bottom.

When you're ready to pitch, you can carefully decant a lot of the starter beer. 002 is my house yeast. I'll slowly pour the beer off a starter until I just start seeing the cake being disturbed. I try to leave no more than about 1/2 inch of liquid in the starter. Then I cover it with a piece of foil and swirl the jar until the cake loosens up and mixes with the little bit of starter beer I left behind. The slurry then goes into the wort.

Biomass yield is directly proportional to extract for the most part. For a quick estimate each gram of extract will produce about 1 billion cells.

Here's my calculator that shows growth over time:
http://www.woodlandbrew.com/2015/02/starter-calculator.html

The typical starter will yield about two fold. An ale pitch rate will yield ten fold. Maybe that's what you had in mind?

zoomzilla said:

This is English ale yeast WLP 002. I used 10/1 ratio DME to water boiled and cooled. The stir plate worked flawlessly and I covered it with foil and let it go three days and this was the end result. It seems like far too little. Does this strain of yeast not reproduce as much as others or was I just expecting too much. I would estimate that there's about 3 or 4 times as much yeast as was in the original vial. I guess I thought I would have at least a ten fold increase.

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I am having a similar issue in doubting my final yeast cell count vs what the starter calculators say I should expect. I have always used yeastcalc or brewersfriend to calculate my step up and starters.

Using the calculators, I performed 3 step ups from about 3 ml of 4 month old rinsed packed yeast (~12B cells @~20% viability equates to ~2.4B starting cells). I did a 150ml step at 1.025 (shaking), then a 500 ml step at 1.032 (stir plate) then a 1.75L step at 1.037 (stir plate). According to the calculator's I should have 300B cells, however, after cold crashing and decanting, I had about 20-25 ml of pure packed yeast in my flask to pitch. Even at a density of 4.5B cells per ml that would only be about 100B cells when measure based on volume. How does one reconcile these differences?

troglodytes said:

I am having a similar issue in doubting my final yeast cell count vs what the starter calculators say I should expect. I have always used yeastcalc or brewersfriend to calculate my step up and starters.

Using the calculators, I performed 3 step ups from about 3 ml of 4 month old rinsed packed yeast (~12B cells @~20% viability equates to ~2.4B starting cells). I did a 150ml step at 1.025 (shaking), then a 500 ml step at 1.032 (stir plate) then a 1.75L step at 1.037 (stir plate). According to the calculator's I should have 300B cells, however, after cold crashing and decanting, I had about 20-25 ml of pure packed yeast in my flask to pitch. Even at a density of 4.5B cells per ml that would only be about 100B cells when measure based on volume. How does one reconcile these differences?

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How long did you leave the starter at each step? For old cultures, I have had to wait up to 48-72 hours for the yeast to spring into action.

The 1st step sat for about 5 days until activity appeared to stop, I did not decant that step and added .5L (the 2nd step) to the flask to have enough liquid volume to use my stir bar. The 2nd step sat on the stirrer for about 3 days until complete and was then chilled in the fridge for 2 days and decanted. The 3rd step was on the stirrer for 3 days, and that was then chilled in the fridge for 3 days and then decanted to pitch into my brew last night.

All in all, I started to step up everything 16 days ago, which is the amount of time it takes to step up some dregs from bottle harvesting, so I figured I would be fine with a (relatively) high amount of viable starting cells.

I ended up pitching late last night and have noticed a longer lag time than usual. I figure its got to be due to a low pitch count, but I'm wondering how my pitch count could be so low with the steps taken.

What type of yeast? What water are you using to make the starter wort? Any nutrients added to starter?

Wy1007 3rd generation. Using boiled tap water, no nutrients added.