Torulaspora delbrueckii

I started my first fermentation using Torulaspora delbrueckii that I got from White Labs WLP603
Seeing as there are not that many people using this genus of yeast I thought I’d start a thread devoted to it.
I have my first batch of beer going at the moment using Torulaspora (pronounced toe-rule-a-spore-a).

This blog post by Dave Bleitner of Off Color Brewing is one of the most informative about the genus.
“Our early trials of beers utilizing mixed fermentation including Torulaspora yeast featured unique notes of fruit cocktail, specifically lychee, papaya, apple, peach, apricot, and pineapple. Some of these fruit notes are uncommon in beer fermented with only Saccharomyces strains as they derive from certain types of ethyl esters, ethyl decanoate and ethyl dodecanoate.”
If that isn’t tantalizing enough for you to try how about the fact that…
“Domesticated Torulaspora yeast is limited in its ability to ferment beer as it cannot metabolize maltose, the main sugar contained in beer wort.* Because of this, domesticated Torulaspora yeasts will only create a partially fermented beer in standard brewers wort when mono-fermented. Once it metabolizes the sucrose, glucose, and fructose, fermentation halts. Torulaspora’s ability to ferment simple sugars but not common beer wort sugars is likely a reason it has found some use in wine but not beer. In order to complete fermentation and create a standard strength beer, the wort must be mixed fermented with a yeast that can metabolize higher chain sugars. This is not as easy as it sounds, as mutual inhibition exists between these two strains when competing for nutrients in the same beer wort.*”

My plan from the beginning was to do a mixed fermentation as suggested by White Labs. “The yeast species Torulaspora delbrueckii is traditionally a longer fermentation and slower attenuator. This strain should be used in a mixed fermentation.” My executed plan was to not make a starter and to pitch directly in a 1.056 OG Sauvin Saison that my LHBS has a kit for.
I was then going to harvest the Toe-Rule from the primary before going to a secondary and introducing a saison strain of yeast. This proved to be a poor plan because the yeast is not behaving like anything I have experienced.
First, it was very slow to take off. It took a solid 2 days for any activity to begin. Then when it did begin a mini krausen was formed and the beer gravity dropped by teeniest tiny amounts each day. Via my Tilt hygrometer I am used to yeast taking off like a rocket and accelerating. Instead this was dropping .001 each day and not speeding up. Then on day 3 of active fermentation the krausen disappeared. This I found worrisome but just I was thinking of starting a started of saison yeast to save the batch, boom, the krausen reappeared. I took this time to harvest off of the krausen.
Excited that something was happening again I started to worry again because the TILT was showing massive drops in gravity now. “Did I just harvest a secondary infection?” I guess I won’t know until I pitch what I harvested but I think that the answer is that the TILT cannot function properly with this yeast. Just going blindly by the TILT in the last 8hrs the gravity dropped from 1.028 to 1.004. This is not possible with this strain. In looking at what is actually going on the krausen has now become a dense matt and the TILT is pinned and cannot move. This matt looks different then most I have seen as it is almost like all of the trub is now on the surface. It is looks completely healthy and active and nothing like a Pellicle.

This is a really great read. One thing that comes up is that an increase in oxygen is needed to really push fermentation with Torulaspora
https://www.brewmasterjack.com/blog/our-experiment-with-torulaspora-delbrueckii

I bottled my Torulaspora today. I think that I failed in making a beer from it however. I made a starter and got a very slow initial fermentation as advertised. About 4 days in my krausen dropped after only dropping 5 points. Then I got a second krausen and the rest of the fermentation finished in 2 days.
I wrote to white labs because I thought I was pretty good with sanitation and I was surprised that I would have a secondary infection that could finish that fast.
The finished beer it interesting but not what I wanted. It has a nice tart quality but not a POF+ quality that I would associate with the wild saison I was going for.
Whatever I harvested from this batch here might be nice in a cider. I will try in a mixed fermentation with some more standard saison yeasts.

Glad your doing the work so we don’t have to :blush:

1 Like

:grin: