Thoughts on pitching starter that reeks of diacetyl.

[twigboy2000]

Anyone had this happen? It's a vial of White Labs Kolsch that I stepped up at room temp. Vial was expired in Nov 2010, but was lost back in the collection.

It's stepping up and attenuating, but the popcorn butter aroma is fierce.

Crash, decant and step again or throw it out? Thoughts?

-chuck

 

[ACbrewer]

if you have the LME/wort material, I might do the decant and try one more time at a starter. If that still has diacetyl, I'd toss it. Someone will post the most likely cause of the diacetyl and then you can go from there on that suggestion. - I think it is a poor fermentation - low aeration, lack of yeast clean up, etc. Although it might also be the signal of an infection - hence my thought of 'decant and try again' and if that still ahs the diacetyl, toss it.

 

[twigboy2000]

Yeah, the wort isn't a problem. I do all-grain mash with a french press to get starters when I don't have leftover wort canned from a previous batch.

I decanted and stepped up last night so we'll see how it goes. It's on a stir plate so I should know something soon.

-chuck