03.03.19 Q&A about our kveik isolates
Over the past few months I’ve received some questions about our kveik isolates (both liquid and dried). As some of you purchased our dried kveik back in late January/early February for our pre-order to be shipped out this week, I wanted to share a summary of the Q&A here:
Q: Why do you sell isolates and not the original kveik cultures?
A: First of all, you can only really get true kveik (a mixed culture of different yeast strains and sometimes bacteria and wild yeast) from a Norwegian homebrewer so we encourage you to do that instead of from us. Each time kveik is shared the ratios of each strain will likely shift.
In general, there are pros and cons to selling isolates vs. mixed cultures. Using isolates allows for a higher degree of control during propagation, resulting in a more reproducible flavor profile. Obviously mixed cultures give more complexity in your beer with a full array of flavors, but getting the correct ratios is challenging even if going back to the original freezer stock every time. In addition, sometimes the lactic acid bacteria in kveik cultures can result in unwanted souring unless enough hops is used.
What we think is cool about selling isolates is now you have the opportunity to combine different ones together in the same beer! This experimentation is what we are all about and will lead to new combinations of yeast that have never been used before. We did a collaboration brew with Imperial Yeast, Lanikai Brewing, and Everybody’s Brewing using our Ehwaz, Fehu, and Gebo strains in the same beer with great results.
Q: Do you have any recommendations for optimal fermentation?
A: Yes, there are a few rules here that should be followed:
- Use a sufficient amount of yeast nutrient (even double the recommended amount is ok), especially if you are using a low gravity beer below 1.050. The reason for this is because these yeast are adapted to a high nutrient environment.
- Properly oxygenate your wort, especially if underpitching (with a recommended target of 10–12 ppm).
- Ferment in the recommended range of 72-95°F (or 22-35°C), as going lower than this could result in sluggish fermentation, and going higher may push the yeast to their brink. We recommend around 85 °F (30°C) or towards the upper range if going for more explosive flavor profiles.
- Use these yeast with higher gravity beers above 1.050 for optimal fermentation.
- Make sure to do a yeast scream when pitching your yeast! 🙂
Q: Have you brewed with these yeasts at lower or higher temperatures than what you recommend on the packaging?
A: Yes, the recommended temperature is between 72-95°F (or 22-35°C), but we have brewed as low as 60°F. At lower temperatures, the fermentation speed will be slower and the flavor profile will be cleaner without as many esters being produced. We have not brewed above 95°F but in test tube experiments in the lab these yeast will grow as high as 104°F (40°C), but are good as dead above 109°F (43°C).
Q: Could you please tell me a bit more about the dried kveik you have for pre-order now? You mention it is 1 gram of dried yeast, but most dried yeast packets I’m aware of are in the 11 gram range. Is your product intended to be used like traditional dried yeasts in that you rehydrate the content of the packet and then pitch? Or are you expected to build up a starter using the 1 gram and go from there?
A: First, kveik is not ordinary yeast and should be severely underpitched to achieve the best flavor profile from the yeast. 1 gram of dried kveik is about 10-20 billion cells depending on the strain and exact propagation conditions so we’re talking about underpitching by about 10-fold. One gram is what traditional Norwegian homebrewers use and we are trying to stay true to this recommended pitch rate. You may notice a lag of up to 24 hours before fermentation fully takes off.
Second, no this product is not intended to be used like traditional dried yeasts so there’s no proofing required. There are a few options once you receive the dried kveik, depending on what beer you are making, how much flavor you want from the yeast, and time before usage.
1. Make a starter to build up the cell count and allow the cells to get “primed” for fermentation (this will allow for a more reliable fermentation with full attenuation but at the expense of extra flavors).
2. Pitch the dried kveik directly into your well aerated wort (this will maximize the flavor profile but there’s always a chance the yeast will stall out and not fully attenuate if the conditions are not ideal, such as too low yeast nutrient, not enough dissolved oxygen, or too low/high a fermentation temperature).
3. Freeze the kveik for later use if not using soon (will keep just fine in the fridge, but freezing is recommended for long-term storage).
Q: Why are you guys called Mysterium Yeast…oooh trying to be mysterious or something?
A: The only thing mysterious about us is the yeast. We try to describe the yeast as well as we can to give brewers the best results. Also the original definition of “mysterium” is “a substance seen as an elemental or pure form of something else.” We like this name because we are acknowledging that we sell isolates of kveik and not true kveik.
01.30.19 Dried kveik available
We now have a limited amount of dried kveik available for pre-order to be shipped out in early March 2019! Check back here for more details.
10.17.18 One year anniversary SBL blog post
Taken from the first Sleight Beer Lab blog post:
A new development in my lab is another one I did not anticipate from the beginning: yeast propagation. Earlier this year I learned about and started playing with some farmhouse yeast strains from Norway (“kveik”) and other countries (a shout out to Svein for sharing these with me, Milk the Funk brewing community for sharing information, Lars for introducing these to the world, and to the traditional farmhouse brewers for sharing!). These yeast are remarkable in their ability to ferment quickly, produce amazing tasting esters (fruity flavors), have no off-flavors at high fermentation temperatures, and can tolerate high ethanol concentrations which means you can use them to make high gravity beers! One tasty brew I made with a kveik isolate was a hazy IPA that had some interesting tropical fruit flavors (see the label I made for this homebrew below). I realized that more people needed to know about these strains so decided to offer them at small scale. We now offer four unique isolates of kveik and other farmhouse strains from our Mysterium Yeast trade name. We’ve now sent out homebrew pitches to several homebrewers and just did our first pro pitch that will be on tap tomorrow!