Messed my yeast starter up?

[Hobo]

I attempted to make a starter using Pale DME, 2 liters of boiled water with WLP 570 for a Strong Belgian Ale. When the OG of cooled starter read 1.100, I realized I put the a whole bag of DME instead of 8 oz.

Trying to save it, I diluted the starter with another 2 liters of water (bottled water, not boiled). Overnight it has developed a 3/8 inch layer of foam and smells ‘yeasty’ — Should I start over with a new batch, add another tube of fresh yeast — or let it go as-is? The Belgian Strong Ale should have an OG of 1.072?

 

[nettekdl]

What gravity did you dilute to? And the foam is normal as is smelling yeast, you are after all growing yeast.

 

[IslandLizard]

If you diluted 2 liters of 1.100 with 2 liters of water you've got 1.050. Most starters are done at 1.035-1.040, so you're still a little heavy. It will be fine.

The idea with starters is to expose the yeast to oxygen continuously to coax them into budding, growing new yeast cells. A stir plate is preferred, but intermittent shaking each time you or a member of your household walks past it, works too, just not as well and you've got to watch out for blow off, which puts your diligently cultivated yeast on the countertop.

 

[IslandLizard]

The limit of growth is around 4 times the original yeast count per growing step, so I doubt you're going to get any more yeast with 4 liters at 1.050 than if you just made a 2 liter starter at 1.040. The leftover malt sugars will start to ferment out.

Once it's done growing, are you going to cold crash and decant the starter beer off the settled yeast cake?

BTW, you must have a pretty large starter vessel to hold all that.

 

[Hobo]

Here's a photo at around 12 hours, the OG is reading 1.040
(foil cover removed temporarily for photo)

 

[IslandLizard]

That's a good looking vessel you've got there.^

So how do you swirl it? The yeast needs oxygen to grow more cells. More oxygen (air) is better.

If you have a stainless steel whisk that can be cleaned and sanitized to homebrew standards, you can beat some good air into that. Every hour! Just store the whisk in Starsan in between whipping sessions.