Harvested Yeast Contamination?

[IowaHomeBrewer]

I haven't done a whole lot of harvesting.

I read a lot about the Conan strain, so I bought a vial of The Vermont Ale from Yeastbay.

Made an IPA, and when I started I did a 3L starter. I decanted, poured 1/3 of the yeast into a sanitized mason jar. Pitched the rest into the batch I made.

It has been sitting about 3 weeks, ran out of kegs/bottles so I had to take a week off of brewing, and this weekend I'm making a Marzen so don't plan on using the Conan.

I was just checking on the conan and saw a little dark ring on the surface of the yeast cake.

Does this indicate infection? I've done two harvests but haven't used either yet, so I don't really have a wealth of experience. To be clear, this was not harvested after fermentation of a full beer. There was no hops/trub in this. It was just a light DME extract starter.

I hope it hasn't gone bad, don't want to pay another $10 for a vial.

Here is a picture..

 

[JLeuck64]

It's looks OK to me. I cultivate/harvest yeast all the time and some starters end up with a little dark layer on the top and some don't. Bottom line is they ALL end up making awesome starters the next time.

 

[IowaHomeBrewer]

Thanks for the reply, very encouraging.

I'm going to build up a nice little yeast bank.

If anyone does not do this I recommend reading Marshalls yeast harvesting guide on brulosophy. Really easy to do. So much easier than washing yeast from a fermented batch.

 

[m00ps]

Its not only easier, its better for the yeast. Instead of washing dirty, tired yeast that fermented an entire beer, you get much cleaner and healthier yeast to use for the next starter