Yeast Strain #1: Our Phenolic Strain
The Hefeweizen beer style, even more so than others, has lots to do with yeast. The beer’s haze–its cloudy appearance–is a result of the yeast, which, unfiltered, floats unsuspended in a Hefeweizen. Its flavor is, in large part, defined by its yeast, too. That banana and clove taste? That’s a result of the yeast–and not additional fruit or spices.
KBC’s Hole in the Wall is a traditional, German style wheat ale. It has the distinctive banana and clove character and a slightly tart finish. It appears hazy and almost yellow.
To make a Hefeweizen that tastes traditionally German, our brewers brought in a specialty strain called a phenolic yeast strain. As its name suggests, it generates phenols. Phenols are compounds which give off clove-like or pepper-like flavors. It also produces esters, which give the beer its distinctive banana character.
Yeast Strain #2: Lager Strain
Compared to a phenolic yeast strain, lager strains behave quite differently. Unlike the phenolic yeast strain, we keep our lager strain in-house year round. We use it in two of our flagship beers: the Winter at Noon Dunkel and Two Ski Brewski Pilsner. We also almost always have a seasonal lager on tap.
As far as fermentation is concerned, what primarily separates lager yeasts from ale yeasts is a difference in fermentation temperature and duration. Compared to ale yeasts (like our phenolic strain), lager yeasts take longer to ferment and require cooler temperatures.
Lagers, just like our Winter at Noon Dunkel, have a clean, subtle character. Lagers are clean and subtle beers, in large part, because of the yeast’s behavior. The yeast doesn’t give off ester flavors, which are usually fruity and more assertive.
Yeast Strain #3: Ale Strain
We keep a house ale strain year round. This yeast we use for our Rope Tow Pale Ale, Cloudcroft IPA, Snowslip Stout, and many seasonal ales.
You pitch your lager yeast at a cooler temperature. So, ale yeast is pitched at a warmer temperature. Lager yeast has to ferment for a longer amount of time. Ale yeast doesn’t take as long. The ale strain, also, releases esters. They’re less clean, less subtle, fruitier flavors than those found in lagers.
An interesting thing about this yeast, if you want more estery, fruitier beer, you can pitch this yeast at a warmer temperature. If you feel less is more, you can pitch it a few degrees less.
Yeast Strain #4: The British Ale Strain
Last but not least, we have our British ale strain, which we bring in part of the year. We use this one in our English Major ESB, our Nut Brown, and our Porter.
An ale strain, Cole and Tyler like to ferment it a little higher than our in-house ale yeast. It produces unique, distinctive esters like stone fruit at a higher fermentation temperature, but still comes out nice and clean.
It’s flocculant, also, meaning it leaves clear, transparent beer. According to Tyler, its flavor profile is more mineral-like than other yeast strains. Try the English Major ESB, focus on the finish, and you’ll see what he means.
It’s not often that we have, at KBC, beers on tap featuring all four of the yeast strains we use. Here’s a fun experiment: next time you’re in, assuming you drop by in the coming weeks when these beers will be available, order a sample tray with the Hole in the Wall Hefeweizen, the Winter at Noon Dunkel, the English Major ESB, and the Rope Tow Pale Ale. You’ll taste the differences created, not only by malt and hop character, but by yeast character too, from four different strains.