Sierra Nevada yeast harvesting question

I've harvested yeasts from commercial beers before, but this one has be baffled. The yeast on the left ended up with two different layers.

It was harvested from 6 Sierra Nevada pale ales, all sanitized and handled correctly and then grown on a stir plate in a sanitized erlenmeyer flask. The one on the right is a normally grown culture of another yeast I did for comparison.

What am I looking at? Contamination? Stray yeast or bacteria? Maybe two yeasts with different flocculation rates, maybe one used for carbonating? Took overnight to provide this type of separation. White layer seems denser.

Are you sure its not trub or break, from the starter, somehow? Thats what it looks like.

Just curious, but why harvest from sierra nevada, their yeast is commonly available everywhere for cheap (us-05, wlp001, wyeast1056)?

This was a small 1.5 liter starter made from DME in an Erlenmeyer flask. I've done 42 batches and have never had this occur. I've done batches with the other yeasts, I'm looking for a closer flavor profile to Sierra Nevada, and wanted to try a batch with their actual strain and see if it came closer to the real deal.

Looks like the yeast on the left just flocced better. I don't see any problem using it.

The white stuff on the bottom doesn't appear to be yeast. Looks creamy like cream cheese mixed with a little milk. Sticks to the glass. The yeast is above it. From what I've seen, bacteria infections are above, so I can't figure out what this glop is.

the creamy stuff is beautiful, clean yeast

Beermeister32 said:

I've done batches with the other yeasts, I'm looking for a closer flavor profile to Sierra Nevada, and wanted to try a batch with their actual strain and see if it came closer to the real deal.

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You're wasting your time. If it is one thing SNPA lacks, it is yeast character. I would focus on hops/grain/water (in that order) and stick with a commercial version mentioned above that is well-known to be sourced from SN.