STA1+ yeasties

[Stags]

Hey y’all! I am starting an experiment using STA1+ WLP099 to fire a 40 gallon ferment of UJSSM.

I did a search for STA1 here and only got 4 hits which makes me think yeasties with this genetic variant may be worthy of discussion by this forum.

I’ll share my experiences as it goes along as well.

[bilgriss]

Any feedback yet?

I'd think with a sugar head, the STA1 gene variant wouldn't be that much of an asset, but I'm curious if you have anything to add.

[Tōtōchtin]

I have been looking at trying some WLP644 for some rum experiments. It's nice to have white labs in my home town.

[Stags]

I have been looking at trying some WLP644 for some rum experiments. It's nice to have white labs in my home town.

So jealous. Shipping costs kill me

[Stags]

Any feedback yet?

I'd think with a sugar head, the STA1 gene variant wouldn't be that much of an asset, but I'm curious if you have anything to add.

Yessir. So far run 1 batch. Finished stripping runs on batch 2, hoping to do the spirit run tomorrow night.

Some observations in no particular order:
Attenuation has been excellent.
Ferments seem to be taking a little longer than they did on DADY. I’d hypothesize that for a sugar head like UJSSM most of the secreted amylase winds up working on complex sugars in the corn and as a result the tail end finish can take longer as sugars are continuously freed and then consumed. Would probably be more efficient with a true mash AG.
That said, a few more possible culprits could be dropping temperatures (working to remedy this), learning to manage ph in a bigger fermenter, and a relatively immature culture.

Specifically to WLP099:
I’ve been able to kick the terminal ABV up to 12% with no issues. I have no desire to stress the yeast, just easier to drop 2 25 lb bags of sugar. I haven’t noticed any adverse effects.
It did pick up a beautiful buttery/ toffee/ butterscotch vibe that hasn’t been present in any of my prior UJSSMs.

[Tōtōchtin]

I have been looking at trying some WLP644 for some rum experiments. It's nice to have white labs in my home town.

So jealous. Shipping costs kill me

I'm not jealous of those in San Diego,nice place to be from. I'm in Mexico and the shipping does indeed suck. But friends become mules if they want to visit.
Tōtō

[Stags]

For the experts among us-

I’m thinking there may be merit in relation to my earlier hypothesis that the enzyme secretions from STA1+ yeast can cause sugar heads such as UJSSM to limp along longer than necessary as the secreted enzymes slowly attack unmashed complex starches in the grain.

The only way I can truly think to test this would be to have 2 identically sized ferments- one UJSSM style, one all grain with enzymes. I would propose adding sugar to the UJSSM to achieve the same SG as the AG. As close to identical fermentation conditions as possible. Same pitch using trub harvested from my existing UJSSM.

If my hypothesis is correct, the UJSSM should finish well after the AG on the premise that after mashing there should be limited remaining sugar in the grain compared to the unmashed UJSSM. At which point we can conclude that there’s STA1 may result in higher efficiency and yield in an AG but is unsuitable for sugarhead washes with complex sugar and starch sources present because it takes an inefficient amount of time to finish clean. Thoughts?

[Jimthebrewer]

Yeasts that have the STA1 gene are hyper-attenuating because, as you said, they release an enzyme that cuts down complex sugars to less complex sugars. Not all diastaticus strains have the STA1 gene but in general, diastaticus yeasts do ferment much further than non-diastaticus strains. That makes them beneficial for distilling purposes.

I recently worked with a commercial distillery to develop a yeast regime for his whisky using a Diastaticus Ale yeast + non diastaticus distilling strain that is thermo tolerant that creates an incredible tropical fruit flavour in the new make. Think pineapple and passion fruit.

[8Ball]

… an experiment using STA1+ WLP099 to fire a 40 gallon ferment of UJSSM.

That’s an awful large experiment size. What do you do with it all if the experiment produces crap?

[Stags]

… an experiment using STA1+ WLP099 to fire a 40 gallon ferment of UJSSM.

That’s an awful large experiment size. What do you do with it all if the experiment produces crap?

Drink swill for a few weeks

[Stags]

Yeasts that have the STA1 gene are hyper-attenuating because, as you said, they release an enzyme that cuts down complex sugars to less complex sugars. Not all diastaticus strains have the STA1 gene but in general, diastaticus yeasts do ferment much further than non-diastaticus strains. That makes them beneficial for distilling purposes.

I recently worked with a commercial distillery to develop a yeast regime for his whisky using a Diastaticus Ale yeast + non diastaticus distilling strain that is thermo tolerant that creates an incredible tropical fruit flavour in the new make. Think pineapple and passion fruit.

Curious- what strains did you use? Kveik?

[Jimthebrewer]

No, it was WB-06 and D-53. WB-06 will attenuate highly, give lots of Esters but importantly will give excellent attenuation and D-53 is thermo tolerant so if you can get it up to 30° it will provide tropical fruit.