Lacto grain starter - one good, one bad.

[Brewsit]

In creating my first lactobacillus grain-based starter, I had a lot of uncertainties. I have seen a lot of similar uncertainties out there, so I thought I would share my experience. I did a starter of about one cup crushed 2-row grain with a cup of water at 130 degrees, stirred it in, put foil over it and let it sit for a few days on the windowsill.

I grew impatient and checked it, and noticed that the water level had dropped significantly, so I added some water. Bad idea. It went from a somewhat funky smell to hot garbage/vomit/diapers. It also had some gray fuzzy colonies along with powdery white on top.

I figured it was gone, so I started another one. This time, I reduced the amount of grain and upped the water a little. I set it in the windowsill and checked periodically.

I was worried that the new starter was bad, because I still had funky smells coming out of it, but not as bad as the first.

The original starter continued to smell awful, but changed over time.

A week after I started the second one, I checked them both. The original smelled exactly like a rancid porto-potty. It had grown a weird layer of funk on top. The new one, however, had a very distinct smell of green apples. It also formed white bubbles that I was accustomed to seeing in wild fermentations.

I thought a comparison picture would be appropriate for anyone dealing with the same questions that I had. On the left is the successful starter, and the right is the unsuccessful. Hope this helps.

 

[Brulosopher]

Nice. They both look disgusting . I've played around a bit with souring wort with grains, and I have friends who have made some delicious BW with this method, but we all used whole/uncrushed 2-row. I wonder how these would have looked if you hadn't crushed the grains? Either way, do you plan to use the "good one" in a batch?

 

[Brewsit]

I think from crushing the grain I just gave the bugs more access to something to grow with... otherwise I think I would have probably used some DME? Good question though, I've heard of it being done both ways.

I pulled some liquid off the good batch and threw it in a BW that I started on Sunday. I didn't think the starter would work out so I pitched some WLP677 Lactobacillus delbrueckii initially... after two days going with that I threw in the starter. All of this at around 90-95 degrees.

The thing was so violent at first that it blew white foam out the top of my airlock (that's with 5 gallons of headspace in a 60L fermenter) so I had to switch to a blow off tube. It's been 24 hours since I pitched the grain starter, I'll post some updates on how it goes.