Step-up Starter Help, WY#1335

silentknyght · October 2, 2012, 3:44pm

Much to my chagrin, I purchased, smacked, and then opened & used a packet of Wyeast #1335 British Ale II that had a date stamp of 17 Apr 2012. I picthed it into a 1.8 L starter (stir plate), and finally :shock: after 48 hours, finally saw significant yeast activity.

The intent had been to pitch #1335 into a 1.064 IPA. However, after a bit of research, it seems that my packet may have been way old, by liquid yeast standards. Can I make another starter to “step up” from here? If so, is there a simple way to do the math on how much yeast I should have now, and how big a starter to make to get to the next level?

Thanks!

mvsawyer · October 2, 2012, 4:42pm

http://www.yeastcalc.com/index.html

Most calcs assume 10% viability at this point so you would need to make multiple starters.
You can calculate viability by date and put the first 1.8L starter in there to find your jumping off point.

gregscsu · October 2, 2012, 5:11pm

Your initial 1.8L starter will yield 90 billion cells once completed. Punch that info into Mr. Malty and you get a recommendation for an additional 1.16L starter. Personnaly I would cold crash the first starter once complete and make an additional 1.5 - 1.8L starter on the stir plate using that yeast. Yeast calulators become less accurate with yeast age and lower cell counts, better to error on the side of caution with a larger starter.

[attachment=0]$18913936F019C2.jpg[/attachment]

silentknyght · October 2, 2012, 6:10pm

Thanks, Sawyer. I really like the YeastCalc site… It seems really good, but MrMalty gets all the press! Go figure.

Greg, I don’t understand how you got 90 billion cells from MrMalty… I looked & looked, but don’t see that kind of straightforward readout anywhere…

gregscsu · October 2, 2012, 6:21pm

I actually used the Wyeast Calc to get that number.

10% Viabillity is equal to 0.1 Wyeast activator packs.
1.8L equals a 0.47551 gallon starter.
Resulting in 50,250,000 cells per ml.
Multiplied by 1800ml equals 90,450,000,000 yeast cells in your original starter.
[attachment=0]$6680941D3681DDDD.jpg[/attachment]

I have never used the YeastCalc site. I may have to check that out.

y42 · October 2, 2012, 9:17pm

Love that YeastCalc site; and It seems to correlate very well with gregscsu’s advice.

Thank’s for the link!

mvsawyer · October 3, 2012, 4:53pm

I like that it’ll tell you the yeast yield after the batch is finished. That way you know how much you have when you harvest!! Also having three steps for starters is really nice.

y42 · October 4, 2012, 11:51pm

Has anyone checked the accuracy of the YeastCalc numbers?

silentknyght · October 6, 2012, 1:05am

A follow-up question.

All yeast starter online calculators evaluate the yeast counts by starter VOLUME, but don’t seem to be so consistent on OG.

So, if I add 4.5 ounces of DME and to a 1.5 L starter volume that, post-boil, becomes 1.3 L… how does that affect yeast cell counts? Would simply adding 0.2L of boiled-and-cooled water really result in an extra 10 billion or so yeast? Or would I need to add an appropriate amount of DME, too?