10 Gallon Batch - First Time Making Starter

I am going to brew up a 10 gallon batch of Biermuncher's 'Helles Belles' this weekend. I have never made a starter for any of my beers, but have decided to start doing so. I have a 2L flask and just got my stir plate from stirstarters.com today. With that said, I am totally confused on what to do. Most everything I've read says '2 cups of water to 1/2 cup dme for 5 gallon batches'. Do I just double this amount? Is my 2L flask big enough for a 10 gallon batch? Do I use both smack packs?

Obviously, any and all help would be greatly appreciated. I've tried to do some research but can't seem to find a definitive answer as to how to handle a starter for a 10 gallon batch.

Thanks!

Check out mrmalty.com and yeastcalc.com for information and their calculators.

A good ratio for ~1.040 wort is 10g DME : 100ml(/g) water. Really, that's 10g DME covered up to 100ml. Yes, DME by weight, not volume.

Your 2L flask is probably not big enough for a single starter for a 10g batch. I'm about to make 2 starters for 2 5g splits from the same 10g 1.068 batch, in which I'll do a 1L->2L stepped starter for each 5g split; this will be a bit more yeast (~400 bn cells) than I would ideally like (~340 bn cells), but it'd be in no way over-pitching. By that, I mean I'll do a ~1L starter from the vial to completion (~36 hours), then crash and decant the spent wort, then do a ~2L starter to go, in total, from the ~85b cells estimated viable cells in the ~2 month old vials to ~400 bn cells. Then I'll save that in the fridge and do the same 1L->2L again for the other strain for the other 5g batch.

yeastcalc.com is your friend.

Also, knowing that that standard ale pitch rates are 0.75m cells / ml wort / 1°P and standard lager pitch rates are 1.5m cells / ml wort / 1°P.

Thanks for the help. I will check out the yeastcalc.com website and look into getting another flask or using a growler in the meantime. Do you all think I need 2 stirstarters or is that overkill?

Homebrewing: as expensive a hobby as you let it be.

As I've gone to 10g batches, I usually split batches into two 5gl-s with different yeasts, but sometimes using the same yeast for the whole batch, and instead varying flavor/spice additions or dry hops or fermentation temps or something else. While I'd *ideally* want two stir plates for the cases where I do differentiate by yeast, I can usually serialize the starters over the course of a week leading up to brew-day … classic space vs. time tradeoff. Once the first starter is done, it'll go into a sanitized mason jar in the fridge, and get pulled out at the start of brew-day for use. I would suggest getting a larger (4/5/6L) flask before getting a second stir-plate, especially/of course if you want to do lagers.

Also, understand the relationship between inoculation rate and yeast growth; if you just try to pitch a smack pack or whatever into 6L of starter wort, you don't get anything close to the results of a stepped starter.

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

The links from yeastcalc.com

The book /Yeast/ by Zainasheff and White.