Kveik — Old Yeast for New Beers


Der Text ist auch in deut­scher Über­set­zung ver­füg­bar.
The text is also avail­ab­le in a ger­man trans­la­ti­on.


Some­what unex­pec­ted­ly, a fami­ly of Nor­we­gi­an farm­house yeasts have burst onto the brewing sce­ne in recent years. Kveik has not yet beco­me a hyped fashion, but it seems almost about to. So what is kveik? And whe­re did it come from?

Until about 150 years ago, most far­mers in nort­hern Euro­pe bre­wed their own beer, from their own grain, for their own use. And all the­se bre­wers had their own yeast, becau­se the­re was no alter­na­ti­ve. Moder­ni­za­ti­on kil­led this brewing tra­di­ti­on in most pla­ces, but it still sur­vi­ves in iso­la­ted pockets across nort­hern Euro­pe. And in a few pla­ces the yeast sur­vi­ves, too.

The yeasts that the far­mers used were trea­ted dif­fer­ent­ly from the way com­mer­ci­al bre­wers have trea­ted their yeast. Fer­men­ta­ti­on was far hot­ter, and shorter, and the yeast was often dried. Becau­se of this the far­mers had yeast that beha­ved dif­fer­ent­ly from the modern com­mer­ci­al brewing yeasts fami­li­ar to today’s bre­wers. I call the­se yeasts „farm­house yeasts” to dis­tin­guish them.

Over the last five years near­ly fif­ty cul­tures of farm­house yeasts have been collec­ted from farm­house bre­wers in Nor­way, Lit­hua­nia, Lat­via, and Rus­sia. Very likely more cul­tures exist, but have yet to be found.

Localities of Kveik Yeasts (Source: 3)

Efforts have been made to trace the ori­gin of each of the­se cul­tures, and every time the chain ends wit­hin a few links with someo­ne who is now dead. Nobo­dy seems to know whe­re the yeasts came from fur­ther back than a few deca­des, but it’s clear that they have been cir­cu­la­ting in the­se brewing com­mu­nities for a long time. Qui­te pos­si­b­ly a very long time inde­ed.

Ana­ly­sis of the­se farm­house yeasts shows that most of them are Sac­charo­my­ces cere­vi­siae, but not all. All of the cul­tures con­sist of mul­ti­ple strains, but deter­mi­ning how many strains is not easy. To take an examp­le, farm­house yeast #5, from Ter­je Raf­te­vold in wes­tern Nor­way, was ana­ly­zed by yeast labs who sell yeast com­mer­ci­al­ly. They found 2 strains. The Natio­nal Collec­tion of Yeast Cul­tures, in Nor­wich, Eng­land, did a more tho­rough ana­ly­sis and found 8 strains. De Pro­efbrou­werij found 17 strains. The Carls­berg Lab repor­ted­ly found 40.

A lar­ge num­ber of farm­house yeast cul­tures have been collec­ted in wes­tern Nor­way, from Har­d­an­ger in the south to Sunn­mø­re in the north. All of the­se are Sac­charo­my­ces cere­vi­siae yeasts, and all the yeasts are more clo­se­ly rela­ted to each other than to any other yeasts. In other words, they form a sepa­ra­te fami­ly of yeasts. It’s the mem­bers of this fami­ly we call „kveik”.

None of the farm­house yeasts collec­ted from Lit­hua­nia, Lat­via, and Rus­sia belong to the kveik fami­ly. Sur­pri­sin­gly, kveik turns out to belong to the Beer 1 fami­ly of brewing yeasts, tog­e­ther with most Ger­man, Bri­tish, and Ame­ri­can brewing yeasts (and some Bel­gi­an ones). Howe­ver, the kveik fami­ly seems to have been for­med by a hybri­di­za­ti­on event bet­ween a Beer 1 yeast and a yeast that has no known rela­ti­ves. The unknown yeast may have been a wild yeast, alt­hough this is not yet known.

Kveik has several unusu­al pro­per­ties. The most famous is its abi­li­ty to fer­ment very hot wit­hout pro­du­cing off-​flavours. The Voss kveiks can fer­ment at up to 42–43C wit­hout ill effec­ts. Other kveiks pre­fer lower tem­pe­ra­tures, but gene­ral­ly 30C or above.

Kveik also stands out for the speed of fer­men­ta­ti­on. It will often show visi­ble activi­ty wit­hin an hour or two of being pit­ched, and a com­ple­te­ly fer­men­ted wort of 6–9% in 36 hours is not at all unusu­al. And sin­ce kveik pro­du­ces very litt­le in the way of off-​flavours, the beer is per­fec­t­ly drin­ka­ble more or less right away.

All the known kveik strains can be dried, becau­se this was the tra­di­tio­nal way to pre­ser­ve yeast in Nor­way. The kveiks are all non-​phenolic, and non-​diastatic, unli­ke the sai­son yeasts, which belong to the Beer 2 fami­ly. Nor­we­gi­an farm­house ale has his­to­ri­cal­ly been very strong, which is pro­bab­ly why the kveiks have a high alco­hol tole­ran­ce of 13–16%.

The kveik fami­ly is qui­te diver­se, so the fla­vours pro­du­ced by indi­vi­du­al kveiks ran­ge from oran­gey (Voss kveiks), banana/​melon (Stran­da), through mango/​pineapple (Ebbe­gar­den), to mil­ky cara­mel, mushroom, and pineapp­le (Horn­indal). The­re are many more vari­ants, but in gene­ral kveik tends to be more aro­ma­tic than ordi­na­ry brewing yeast and to pro­du­ce tro­pi­cal fruit aro­mas.

The main way to con­trol the strength of aro­ma pro­duc­tion is through the pitch rate. Under­pit­ching gives a stron­ger aro­ma, and no off fla­vours. Fer­men­ta­ti­on tem­pe­ra­tu­re also affec­ts the aro­ma, but less so than the pitch rate. A good pitch rate for a beer of 6–10% is 1 bil­li­on cells per liter.

Kveik can be used for Eng­lish beer styles, as well as many of the modern craft styles. It is par­ti­cu­lar­ly sui­ta­ble for IPA and NEIPA, sin­ce the tro­pi­cal aro­mas from the yeast fit well with tho­se from modern craft hops, and the fast fer­men­ta­ti­on and matu­ra­ti­on allow the beer to be released fresh. Of cour­se, kveik can also be used for the tra­di­tio­nal styles, such as heim­ab­rygg and kornøl. Some­what counter-​intuitively, kveik will not pro­du­ce typi­cal sai­son beers, becau­se it is neit­her dia­sta­tic nor phe­no­lic.

Reu­sing kveik is easy: refri­d­ge­ra­ted slur­ry will keep 6 mon­ths wit­hout dif­fi­cul­ties. It can be stored at least two years, but must then be pro­pa­ga­ted befo­re use to ensu­re it is fresh. Farm­house bre­wers usual­ly dry it, in the oven or using gent­le heat such as a shoe rack or a mushroom dri­er. In dried form it can be fro­zen and will then keep for at least two deca­des, pos­si­b­ly lon­ger.

If reu­sing the ori­gi­nal kveiks con­sis­ting of many strains some care must be taken to pre­ser­ve the com­po­si­ti­on of strains, or the cul­tu­re may chan­ge beha­viour. The safest way to do it is to har­vest the yeast in the same way as the ori­gi­nal owner. Con­sult the yeast table to see how.

It’s also recom­men­ded to keep track of which cul­tures were har­ve­sted from which bat­ches of beer, and to only reu­se the yeast from the best bat­ches. This is what the farm­house bre­wers them­sel­ves do, and it has the effect of pre­ven­ting infec­tions from taking hold, and encou­ra­ging the cul­tu­re to deve­lop in desi­ra­ble direc­tions.

Many bre­wers are con­cer­ned about ris­king bre­we­ry infec­tions if they use kveik, but remem­ber that this is a Beer 1 yeast. It is neit­her dia­sta­tic nor phe­no­lic. So if an „infec­tion” were to hap­pen, and some kveik cells get into a beer whe­re they are not sup­po­sed to be, the effect is unli­kely to be at all noti­ce­ab­le.

The word „kveik” is one of several Nor­we­gi­an dialect words for yeast, and is the most com­mon word for yeast in the inland distric­ts of sou­thern and wes­tern Nor­way. Ety­mo­lo­gi­cal­ly it comes from the same root as the Eng­lish „quick” in the sen­se of being ali­ve. In Nor­we­gi­an dialec­ts it can be used to mean both breat­hing life into some­thing (such as ligh­t­ing a fire) and yeast. In Voss in wes­tern Nor­way it’s beco­me com­mon to refer to shop yeast as „gjær”, while the farm­house yeast is cal­led „kveik”.

Expe­ri­en­cing the brewing cul­tu­re that the­se yeasts come out of is very dif­fi­cult. Even just tas­ting the tra­di­tio­nal beers is very hard, becau­se they are not sold com­mer­ci­al­ly. The­re is, howe­ver, one solu­ti­on: Norsk Kornøl­fes­ti­val, a fes­ti­val dedi­ca­ted to tra­di­tio­nal beers, held in Horn­indal in wes­tern Nor­way in Octo­ber. Here the farm­house bre­wers ser­ve their beers and talk about them, and some even hand out sam­ples of the fami­ly kveik.

The use of kveik in wes­tern Nor­way has been in a steep decli­ne over the past cen­tu­ry. Many of the cur­rent cul­tures were collec­ted from bre­wers who had stop­ped using them, but were still pre­ser­ving them in their free­zers. Youn­ger peop­le in the­se distric­ts seem to most­ly favour modern home brewing, alt­hough with the recent sur­ge of inte­rest in tra­di­tio­nal beer it’s pos­si­ble that this may be chan­ging.

Out­si­de the tra­di­tio­nal brewing regi­ons the use of kveik has been gro­wing rapidly over the past five years among both home bre­wers and com­mer­ci­al bre­wers. At the time of wri­ting Ratebeer.com lists 423 com­mer­ci­al beers bre­wed with kveik, but the list is not com­ple­te. A num­ber of com­mer­ci­al labs now sell kveik, such as White Labs, Impe­ri­al Yeast, Ome­ga Yeast, the Yeast Bay, Fer­men­tu­um Mobi­le, and Escarp­ment Labs. In addi­ti­on, many enthu­si­asts sha­re dif­fe­rent kveik (and other farm­house) cul­tures with each other through online forums.

Rese­arch on kveik and the other farm­house yeasts is still ongo­ing. Work is under way to learn more about the ori­gin and beha­viour of the non-​kveik farm­house yeasts. Work is also ongo­ing to stu­dy the brewing pro­per­ties of kveik in more detail.

Two farm­house yeast cul­tures have been collec­ted from eas­tern Nor­way, which is geo­gra­phi­cal­ly divi­ded from wes­tern Nor­way, and the­re­fo­re had a dif­fe­rent brewing tra­di­ti­on. Not­hing is known about what kind of yeast farm­house bre­wers in eas­tern Nor­way used, but it is hoped that the­se two cul­tures can give us an ans­wer, as they come from dis­tinct regi­ons: Hal­ling­dal and Tele­mark.

The book will be released soon at Brewers Publications

What future looks like for kveik is dif­fi­cult to judge at the moment. The collec­ted cul­tures have been depo­si­ted with the Natio­nal Collec­tion of Yeast Cul­tures in the UK, and also many other yeast labs, so the yeast its­elf should be gua­ran­te­ed sur­vi­val. The brewing tra­di­ti­ons in wes­tern Nor­way were on the decli­ne, but it is pos­si­ble that the increa­sed inte­rest both in Nor­way and abroad may rever­se the decli­ne.

In com­mer­ci­al brewing kveik seems to be hea­ded for a hype peak, and the ques­ti­on is what lies on the other side of the peak. Many hyped trends peak and disap­pe­ar, but my pre­dic­tion is that in this case the yeast its­elf is such a use­ful tool for bre­wers that even after the exci­te­ment dies down com­mer­ci­al bre­wers will con­ti­nue to use the yeast, sim­ply becau­se it pro­du­ces good and uni­que beers in a high­ly cost-​effective way.


Refe­ren­ces:

  1. Preiss et al, 2018. „Tra­di­tio­nal Nor­we­gi­an Kveik are a Gene­ti­cal­ly Dis­tinct Group of Domesti­ca­ted Sac­charo­my­ces cere­vi­siae Brewing Yeasts.” In Fron­tiers in Micro­bio­lo­gy, Evo­lu­tio­na­ry and Geno­mic Micro­bio­lo­gy, 12 Sep­tem­ber 2018. doi.org/10.3389/fmicb.2018.02137
  2. Gar­shol & Preiss. 2018. „How to Brew with Kveik.” MBAA TQ vol. 55, no. 4, p 76–83.
  3. Yeast regis­try: http://www.garshol.priv.no/download/farmhouse/kveik.html

All Pho­tos by Lars Gar­shol. The pro­duct images are from the web-​Sites of the pro­du­cers.

Schreibe einen Kommentar