NTNU main entranceThe Norwegian University of Science and Technology (NTNU) inTrondheim started doing research and courses on brewer's yeast alittle over a year ago. I figured this was good timing, and askedthem if they wanted to do research onkveik (Norwegian farmhouse yeast). The answerfrom professor PerBruheim was immediate. Yes! They would love to have some Norwegianyeast to work on. So I've been sending them all the yeast I could getmy hands on.This spring the first fruits of their research emerged: the thesis"Characterizationof genotype and beer fermentation properties of Norwegian FarmhouseAle Yeasts", by Truls Rasmussen. It's a master's thesis whereTruls has looked at the various collected yeasts from several pointsof view. The whole thing is 164 pages of quite intensely technicalbiochemical detail, but I'll try to explain the highlights here.The cast of characters Some of the charactersI guess many people don't know all of these yeasts, so I'll give aquick overview here so that you can refer back here and get a sensefor which yeasts are which. I use the names used in the thesis herefor simplicity. I'm listing these by geographic origin south-to-northorder along the Norwegian west coast.
- Sigmund, the first kveik I ever met, from Voss. The story of brewing with Sigmund and collecting his yeast. Commercially available from The Yeast Bay and Fermentum Mobile.
- Rivenes, also from Voss, collected a few years before.
- Wendelbo, from Lærdal. I'm told this yeast has been used since forever in the valley. I have not yet met the brewers, unfortunately.
- Muri, from Olden. This yeast was apparently last used in the 1990s and then left in a storehouse on the farm. Andreas Muri is a modern homebrewer, and in 2015 got the idea of trying to revive the yeast, which he managed to do. It's been sold commercially as WLP 6788.
- Raftevold, from Hornindal. The story of me brewing with this yeast.
- Gausemel, also from Hornindal. Terje Raftevold got his yeast from Olav Sverre Gausemel 20 years ago, so these are almost the same. I've met Olav Sverre briefly.
- Stranda. Stein Langlo in Stranda had stopped brewing with this kveik, and NCYC just barely got it to grow. Back story. Sold commercially as OYL-057.
Some people have been skeptical of this whole kveik story, claimingthat no way can people have kept these yeasts going for centuries, andthat most likely this is normal bread yeast like the farmhouse brewersuse in regions where there is no kveik. To check that, Trulsincluded
Idun Blå, the Norwegian commercial bread yeast.Finally,
Finland 1 is a yeastthat Mika Laitinen collected froma very old sourdough culture from the sahti area in Finland. He brewedwith it a few times and eventually got a yeast that produces somethingnot unlike modern sahti. Whether it was ever used to brew sahti forreal we don't know.The yeasts referred to as Lithuania 1-4 were collected fromLithuania by me, but since I didn't manage to get permission from thebrewers to do research on them we've anonymized the results. Don'tbother asking me which yeasts they are, because I won't tell you. Notbefore I can get permission from the brewers, which may never beforthcoming.Overall, a pretty diverse bunch.Cultures vs strainsMost of these yeast cultures contain more than one strain of yeast.Sigmund's has 3, Rivenes's has 7, Hornindal has8, Muri has 2, and so on. The only one that I know has just one isStranda. The thesis ignores this, which makes interpreting the resultsa little harder. We know that for example in the Hornindal andGausemel kveiks there are strains which are not related to one anotherat all. So it's possible that if they'd picked other strains fromwithin these cultures they would have gotten different results.Eeeek! Bacteria! The first feedback I got was pretty immediate. Per wrote backsaying "there are contaminants in these cultures!" It turned out therewere bacteria in the Hornindal kveik, but I alreadyknew that these bacteria were supposed to be there. So I wroteback telling Per not to worry, and to make sure to test withthe bacteria.From the photos I can see why Per and Truls were worried. Thebacteria produce a yellowish glassy slime that really doesn't lookvery good. The taste is amazing, though.Growth ratesThese were pretty similar. Sigmund's Voss kveik was the fastest, afinding that will not surprise the many people who have seen thisyeast overflowing their Erlenmeyer flasks when growing it. The slowestwas Stranda. Total variation was about 20%, so not huge.Flocculation (Taken from the thesis, with permission.)They tested how well the yeasts flocculate, that is, how fast theysettle down to the bottom after fermentation. Hornindal flocculateslike a real hero, with 100% of cells settling out within 5 minutes,and Stranda and Muri also perform pretty well. As we found in our owntests, the Idun Blå commercial bread yeast is a really crappyflocculator, with about 5% having settled out after 5 minutes. Moresurprising was that they found that Sigmund's Voss kveik alsoflocculated poorly (30%). I've watched that literally settle out whileI was looking at it, so how they got this result I really don't know.The odd thing is that other people have been getting the same result.Sigmund's kveik consists of at least three related strains, andit's possible that one of these is a poor flocculator. It may be thatNTNU grew that one, while normally it's not dominant. Perhaps.Genetic comparison (Taken from the thesis, with permission.)By analyzing the DNA of these yeasts, Truls was able to build aphylogenetic tree of all the yeasts. Basically, that shows whichyeasts are the most closely related, and which ones are further apart.(A word of caution here: there are several issues with this tree andwith the genetic data in general, so all of these results must beconsidered tentative at the moment. That goes for the next section,too.)The first thing we see from the diagram is that the Lærdal kveik(Wendelboe) is an outlier. All the other yeasts are more closelyrelated to each other than they are to that one. So that yeast is areal oddity.Next, the yeasts split into two groups. A small group of three:Terje Raftevold's Hornindal yeast, Olav Sverre Gausemel's yeast alsofrom Hornindal, and Svein Rivenes's from Voss. Terje got his kveikfrom Olav Sverre 20 years ago, so it makes perfect sense that thesetwo should be close. They're very nearly the same yeast. SveinRivenes's probably shouldn't be here, though,since we already know that it's very closelyrelated to Sigmund's.The other group has one outlier: Idun Blå. The rest are moreclosely related to each other than to that one. The group is furthersplit into two, one smaller group (Lithuania 1, Finland 1, Lithuania4), and a bigger group (Stranda, Sigmund, Hornindal, Muri, Lithuania 2and 3). Stranda, Sigmund, and Horninal form a small cluster.So ... what does this actually mean? Well, most of all it meansthat these yeasts are extremely diverse, and that the yeasts don'tcluster by what region they came from. A Finnish yeast sits in betweenthe Lithuanian ones, and some Lithuanian ones are closer to someNorwegian ones than to the others. Even within Norway thegeographical relationships don't hold. Stranda, furthest north, is themost similar to a yeast from Voss, furthest south.That fits well with what I've seen after this study began. WilliamHolden collected two kveiks from Stordal in Sunnmøre. It's a verysmall village (population 1020), so you'd expect it to have no morethan a single yeast strain, but the two cultures produce dramaticallydifferent beers. They don't seem to be related at all.Species identificationTruls also uploaded the genetic sequences to an online tool thatfrom the genetic data predicts what species it is. In general, if theanswer has a certainty of less than 80%, you should consider thespecies unknown. Curiously, the tool can't determine the species of noless than four of the yeasts. We'll get back to what that might mean.The table below shows the results.
Always loved this song--many of us did, judging by the amount of musicians that covered it--everyone from Willie Nelson, The Grateful Dead and Gordon Lightfoot to name a few. What i didn't realize is that although Janis Joplin was the one who made it famous, it was Kris Kristofferson who wrote it along with music producer Fred Foster...
Below you will find several of my favorite versions of the song, beginning with my number one, Janis Joplin's classic and probably her most famous song, which sadly came out posthumously just a few days after Joplin's death. Kris Kristofferson, who was at one point Joplin's lover, did not even know himself that it was to be included on her album Pearl until it was released.
Janis Joplin's version, Me and Bobby McGee
I discovered this wonderful version by these four greats: Kris Kristofferson, Willie Nelson, Gordon Lightfoot, and Ronnie Hawkins.
Here's a nice duet with Sheryl Crow and Kris Kristofferson
The Highwaymen version by country greats Johnny Cash, Willie Nelson, Waylon Jennings and Kris Kristofferson
And the simple gem of a version by Gordon Lightfoot
This is the first version Kristofferson originally gave to Roger Miller to perform. .
The song was actually based on a true story of a crush Foster had on a secretary named Bobbie McGee. Here is the history.
e2b47a7662
