Testing viability of commercial sour dregs

[Trippel-A]

We were going to brew a sour, so we bought a bunch of unpasteurized, unfiltered commercial sours and drank 'em. We poured the dregs into sanitized beer bottles, capped them, and put them in the fridge.

Then my brew buddy who was supposed to take the lead on the sour... well, let's just say it hasn't happened yet. We harvested the dregs several weeks ago. Maybe months ago.

I'm thinking those bugs might be dead, and we weren't sure how viable they would be in the first place.

So, my question is this. Can I test the viability of those dregs by creating a starter for them? Does that work with dregs?

 

[wonderbread23]

There are probably some viable microbes. Personally, I'd add maybe 200ml of 1.020 wort (cooled) to each. Let that roll for a week or so and then step it up to 400ml of 1.040 wort. You might see some activity in the second step. You can also taste it to see if it's fermented out.