i made a 3 liter starter yesterday using 9 oz DME. when i added it to the water it turned a gray color. After boiling i let it cool and it’s very dark brown almost black. i used extra pale DME. what causes this?
What strain was it?
Did you add any nutrient to it? How long did you boil it for?
Was this new DME or had it been around for a while? It almost sounds like it had gone bad…
are you sure it wasn’t powdered graphite? Coal Dust?
I say do it again and see what happens.
IME DME does not go bad. It may clump up, but it has a pretty long shelf life. I’ve had LME darken, but not DME.
I’ve not had DME go bad either. However, I keep it sealed and cool. Maybe there was black mold in it?
I’ve had this happen a few times, and it was from the same bag of DME that I’d used when it didn’t happen. I can’t tell you why, but it’s never caused me a problem.
I wonder is some of the DME scorched when boiled. If enough actually carbonized it could well turn the whole starter blackish.
Possible, but when it’s happened to me there was no evidence of scorching.
I’d say do it again. I’d rather start over early in the process (with minimal time and cost) than have to try and manage around a bad batch in the primary or worse yet, the keg.
So you’ve gone ahead and used it?
Yep…how will you know of you don’t try?
True. But I still would probably just dump it and start over since the yeast has not yet been pitched.
Of course, I’ve used old bulging cans of LME before so perhaps I would just go ahead and use it.
I kinda gulped and thought “Let’s find out”. I won that one…that doesn’t always happen, you you always learn something!