Yeast Fun

Originally Posted - Saturday, March 13, 2010

A while back I had mentioned various yeast strains we have been trying and I'd like to elaborate further on our results.

We first started our pilot batches using the Wyeast 3724 which is the Saison Dupont strain. This strain is notoriously finicky and after several batches, only one of which attenuated down to the single digits, we abandoned that approach in favor of a multi-yeast fermentation. There has been speculation that Saison Dupont uses a mixed strain fermentation so this was our way of trying to replicate that approach.

We then began doing small fermentations to assess the organoleptic qualities of various yeast strains. Some contenders were Fermentis T-58 (Chimay variant), WLP550 (Achouffe), Lallemand 71B (wine yeast), and Lallemand Assmanshausen (wine yeast). My goal was a blend in which the Dupont strain was dominant and the other strains playing a secondary role. My other goal was a blend that was repeatable and didn't require a large investment in propagation equipment to maintain multiple pure strains.

The blend we eventually came up with was a Dupont/Assmanshausen/T-58 blend. This required the ability to keep a pure culture of the Dupont strain since this strain is only available in liquid form. And since the other two strain are dry yeast strains, there is no need to maintain these cultures. They also have complementary characteristics. The Dupont strain is a fast starter and will dominate the first 48 hours of fermentation as the temperature rises to the high 70s. The Assmanshausen strain takes 36-48 hours to acclimate and begin fermentation and will take off just as the Dupont strain is stalling out. Also, being a wine yeast, it likes higher fermentation temperatures. One drawback to this strain is its inability to ferment maltotriose so a small amount of T-58 helps to clean up at the end of fermentation. Our results with this blend were very good despite being somewhat cumbersome.

One strain I was rather resistant to try was the Wyeast 3711 French Saison. I eventually did and was impressed with the results. I will tell you more about that next week.

-Gordon