What are the differences between Kveik and Saison yeasts?

[marshbrewer]

I've never drank a beer with either, but on paper the yeasts appear to offer similar characteristics (ability to ferment at very high temps, reasonably neutral). However, the appearance of Kveik yeasts has been greeted with such a positive press I'm guessing they are a game changer. So, other than the obvious (that brewing with a Saison gives you a Saison, a Kveik a Kveik ) what are the main differences?

 

[Clint]

I think Saison yeasts impart a certain flavour and ferment low so really dry a beer out if that sounds right?
My very limited experience with Kveik is very positive....I'm drinking a very young American pale..it's really good but hasn't cleared...it's hazy,not that I'm bothered by that at all...if I tried to brew a hazy beer I probably couldn't!!

 

[An Ankoù]

This is an excellent book with an entire and substantial chapter on yeast. He examines the properties of kveik in depth and makes a comparison with non-kveik farmhouse yeasts including saison yeasts. It seems that most kveiks don't impart what he calls a "POF- phenolic off flavours", while other farmhouse yeasts do to a greater or lesser extent. Also kveiks can usually be dried. while the other yeasts can not.

 

[Rodcx500z]

Cool mate you not live far then?

I think Saison yeasts impart a certain flavour and ferment low so really dry a beer out if that sounds right?
My very limited experience with Kveik is very positive....I'm drinking a very young American pale..it's really good but hasn't cleared...it's hazy,not that I'm bothered by that at all...if I tried to brew a hazy beer I probably couldn't!!

Same as Clint but mine is a bitter, its been in the barrel 2 weeks and will not fully clear other than that its its a great bitter

 

[AdeDunn]

There are even Kveiks out there that can be used to make pseudo lagers, at room temperature with no temperature control..... Kveik is awesome. Saison yeasts are too, but they make saisons, where Kveik can be used to make a whole range of styles, not just kveik.

 

[Ajhutch]

I haven’t used Kveik yeast yet but my understanding is that Kveik is a fast acting yeast but fairly low ester/phenol production. Whereas Saison yeast takes a “normal” length of time, but produces quite distinctive yeast-driven character. Also, Saison yeast is diastatic so will take most beers really dry

 

[JonBrew]

As @Ajhutch has alluded to, in my understanding, one of the main differences is that Saison strains are Phenolic Off Flavour (POF) positive, whereas Kveik strains are POF negative. Both produce Esters though and in the case of kveik this is why they're so popular for producing these hazy fruit juice monstrosities when fermented at high temps.

 

[DCBC]

View attachment 30118
This is an excellent book with an entire and substantial chapter on yeast. He examines the properties of kveik in depth and makes a comparison with non-kveik farmhouse yeasts including saison yeasts. It seems that most kveiks don't impart what he calls a "POF- phenolic off flavours", while other farmhouse yeasts do to a greater or lesser extent. Also kveiks can usually be dried. while the other yeasts can not.

I was going to post.... pretty much exactly this. This book is essential reading for anyone interested in beer, cultural history and ethnography. It also goes into great detail about kveik's (and to a lesser extent, by comparison, saison's) place in the yeast family tree.

But really quickly (and I'm generalising a lot here):

Common features:
- both Saccharomyces cerevisiae (although any given kveik can be 5-6 strains of sac cerv in one culture)
- can both tolerate warm fermentation without fusel alcohol production
- both considered 'farmhouse' yeasts FWIW but that's kind of an artificial category

Differences:
- saison is generally POF+, I think no 'true' strain of kveik is
- kveik tends to be more interesting the hotter it gets up to about 35c or even 40c. Saison can tolerate these temps but it's not optimum range
- most kveiks can survive drying between batches and dry storage for some time
- many kveik strains are extremely flocculant - not sure that's the same with most saisons
- kveik is an extremely fast fermenter and doesn't need any real yeast mop-up time at the end

Feel free to correct me if I'm wrong about any of this :)


EDIT: Of course, of course, the speed of fermentation for kveik is a HUGE difference too (edited above). Many Norwegian farmers bottle or keg after 48 hours. Though we shouldn't take this as meaning that we can necessarily: according to Garshol, some farmers traditionally had/have a clever means of bottle/keg conditioning, which means it's not quite done after the 48 hours. What happens is they package with a couple of gravity points to go and it's often stored cool in a cellar, pretty much flat with near zero yeast activity. Kveik is such a fast-acting beast that all you need to do if you're having a party is take the beer into a warm room and it performs secondardy fermentation in front of your eyes, and will keep doing so for hours, despite often having been poured into a big bowl, which you would expect would purge it of all carbonation. Fascinating stuff!