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Battle Hammer Viking IPA & Kviek Yeast

Kviek Yeast
Perhaps  the biggest brewing trend of 2019 has been the explosion in popularity of Kveik (pronounced Ki-Vike) yeast. Kveik is a group of Norwegian yeast strains that were previously best known for their use in Norwegian farmhouse brewing. Kviek yeast has been used in brewing for over 400 years now, but recently has seen a resurgence in popularity because of some of its unique properties.

So what is so special about Kviek? Primarily it boils down to temperature! Unlike typical ale yeast, which ferments best around 68F, Kviek yeast strains ferment well up to temperatures of 100°F (a temperature that would kill most lager or ale yeast strains).  In fact, the sweet spot for Kviek yeast strains is between 70°F and 95°F  and at high temperatures it imparts little noticeable difference in ester production. The ideal fermentation temperature for a lager is typically between 45F and 60F ; for an ale it is 68F and 72F.  Unlike Kviek, most lager and ale yeast strains produce undesirable off flavors / esters once they exceed their optimal fermentation temperature ranges. If a home brewer does not have the ability to control their fermentation temperature this often times translates to sub par beer.

The high fermentation temperature range of Kviek yeasts has another big benefit, SPEED! You know how cold blooded animals like snakes and lizards move slower when it is cold outside and faster when it is hot? Well yeast works the same way.  When the temperature is high, yeast gets super charged.  It is the reason why lagers ferment so much slower than ales. Using Kviek yeast is kinda like trading in your old 2007 Dodge Caravan for a 2020 Porsche GT2 with a carbon fiber spoiler, reduced weight seats and upgraded suspension package.

Not wanting to drive a Minivan any longer, I figured I would give Kviek a shot and see what all the hype was about.

 

Kviek Yeast Fermentation TemperaturesTEMP: 65–100F (18–38C) FLOCCULATION: MEDIUM-HIGH ATTENUATION: 75–85% ALCOHOL TOLERANCE: 10% Norwegian Voss Kveik Strain. Highly versatile, can be used in a wide variety of beer styles. A traditional Norwegian Kveik strain that has an extremely wide fermentation temperature range. This strain has been traditionally used in Norwegian farmhouse style beers however, due to it’s fermentation temp range can be used in a variety of beers from pseudo lagers, Belgian inspired, and hop forward beers. The possibilities seem endless when fermenting with Loki. On the cool end of the range Loki is super clean; producing little to no esters. On the high end of the fermentation range, 85-95F, it tends to produce a huge fruit ester profile.

Home Brewing with Kviek Yeast

To take full advantage of the Kviek fermentation benefits, I purchased a dual stage temperature controller and an “always on” heating pad for my fermentation chamber (converted chest freezer).  Keep in mind that as yeast ferments it is releasing a bunch of energy as it replicates, digests sugar, pees out alcohol and burps out CO2. In the image at the top of this article, you can see that I set my fermentation temp to 86F and the yeast brought the temperature all the way up to 90.1F during primary fermentation. It is advised that you make sure you keep that in mind as you set your desired fermentation temperature into your temp controller if you happen to use one.

For my first Kviek batch, I fermented a Double IPA and used the Imperial Loki Kviek yeast strain. Here is some of Imperials information on it:

Imperial Loki Kviek Yeast

TEMP: 65–100F (18–38C) FLOCCULATION: MEDIUM-HIGH ATTENUATION: 75–85% ALCOHOL TOLERANCE: 10%
Norwegian Voss Kveik Strain that can be used in a wide variety of beer styles. A traditional Norwegian Kveik strain that has an extremely wide fermentation temperature range. This strain has been traditionally used in Norwegian farmhouse style beers however, due to it’s fermentation temp range can be used in a variety of beers from pseudo lagers, Belgian inspired, and hop forward beers. The possibilities seem endless when fermenting with Loki. On the cool end of the range Loki is super clean; producing little to no esters. On the high end of the fermentation range, 85-95F, it tends to produce a huge fruit ester profile.

I created a yeast starter with the Kviek yeast the night before. The brew day went well with no mishaps. I pitched the wort, placed the fermenter in the fermentation chamber and checked in on it periodically.   The fermenter was already bubbling after just a few hours. I had never seen fermentation begin so rapidly. Primary fermentation concluded in just 3 days which was incredibly fast for a beer with an approximate ABV of 8.5%.  I dry hopped the beer for 3 additional days and then cold crashed for 2 days at 45F. My highest fermentation temperature reached was 91F.

 

Battle Hammer - Viking IPA with Kviek Yeast

Battle Hammer – Viking IPA with Kviek Yeast

I named my first Kviek beer Battle Hammer – Viking Double IPA. It is extremely hoppy, but with a name like Battle Hammer, I figured it needed to be. I had only let the beer condition in the keg for about a week and at this point it is still a little cloudy;  I am hoping it will clear a bit over the next couple of weeks. The beer tastes fantastic; very clean and with no off flavors that might have come from the yeast. I was unable to taste any noticeable difference between brewing with this Kviek Loki yeast to when I had brewed this same beer in the past with a Wyeast 1056 American Ale yeast strain. The beer came out great, my only change would be to perhaps swap out some of my old school hops for some Citra to brighten the hop profile a bit.

To celebrate the beer, I had created a tap handle inspired by it’s Norwegian heritage.

Norwegian IPA - Battle Hammer - Kviek Yeast

Norwegian IPA – Battle Hammer – Kviek Yeast – Tap Handle Being Welded

 

Norwegian IPA - Battle Hammer - Kviek Yeast - Finished Tape Handle

Norwegian IPA – Battle Hammer – Kviek Yeast – Finished Tape Handle

The runes on the tap handle read “IPA” or at least that is what the Google tells me.

I already have another Kviek fermented beer in the works. For this batch I am using the Omega Kviek Hornidal strain. It is going to be a Coconut Milkshake Hazy IPA.  I am hoping that some of the tropical not from them Hornindal Kviek strain take hold in the beer. The hop profile of this beer is far more subtle than my Battle Hammer Viking IPA, so the yeast should have a greater impact on the flavor of this beer.  Here is some information on the Kviek yeast stains put out by Omega.

HotHead

HotHead is Norwegian in origin from the Stranda Kveik. The famous Lars of Larsblog collected it in Norway and then sent it away for isolation. This isolate has a uniquely pleasant fruitiness and an absurdly wide fermentation range, and ferments clean across the entire range. This is great for brewers who want to be energy efficient with temperature control, or who lack temp control in warm climates. It maintains a stable ester profile, and we advocate it’s be used for hoppy American ales.

Attributes:  Med-High Flocculation, 75-85% Attenuation, : 72-98° F Temp Range, 11% ABV Alcohol Tolerance

HotHead Kviek Yeast can be purchased here for $8.99

Voss Kveik

Voss Kveik is also a Norwegian farmhouse strain from the Gjernes farmhouse which is new to US brewers. It maintains character over a broad temperature range with subtle orange citrus notes that match fruity hops well.

Attributes: Medium Flocculation, 75-82% Attenuation, 62-98° F Temp Range, 12% ABV Alcohol Tolerance

Omega Voss Kviek Yeast can be purchased here for $8.99
Hornindal Kveik

A wonderfully unique Norwegian farmstead Kveik.  Hornindal presents a tropical flavor and aroma of fresh pineapple, mango and tangerine, which complement fruit-forward hops. Add even more dimension to C hops with a high fermentation temperature, intensifying aroma and fermentation speed. Ferments well at 90+° F.

Attributes: High Flocculation, 75-82% Attenuation, 72-98° F Temp Range,  16% ABV Alcohol Tolerance

Omega Hornindal Kviek Yeast can be purchased here for $8.99

 

Sparge Arm

A sparge arm is a piece of brewing hardware used to flush the grain bed with hot water in order to extract any residual sugars left behind in the mash. The sparge arm water needs to be in the range of 168° F in order to liquefy the remaining sugars; if the temperature exceeds 170° F, the brewer many risk pulling excess tannins from the grain husks and causing off flavors and chill haze in the finished beer. Sparge arms are typically constructed of copper, stainless steel, or plastic, and should have some form of flow control so that the approximate flow rate can be set to keep pace with the flow of wort leaving the mash tun (or lauter tun) and heading to the boil kettle.

 

Below are three examples of home brewing sparge arms. From left to right, there is a MoreBeer.com “Ultimate Sparge Arm,” a rigid copper sparge arm, and a fly sparge arm with a stainless bracket. I have used each one of these and am currently using the MoreBeer.com sparge arm due to its versatility, which allows me to integrate it into my RIMS system.

 

You can purchase the sparge arms here:

Home Brewing Sparge Arms

Home Brewing Sparge Arms

Top Fermentation

Top fermentation, or top fermenting, describes the tendency of ale yeast cells to conduct the majority of fermentation on the surface of the fermentation vessel as opposed to the bottom, as is common with lager yeast. Top fermenting ale yeast is typically fermented at a temperature range between 65° F and 75° F; the lower the temperature, the slower the fermentation is carried out.

 

Excessive fermentation temperatures have been known to generate off flavors in beer, and that is why a temperature range of 65° F to 75° F is typically recommended. When a top fermenting ale is most active, a thick head of foam known as a krausen forms on the top of the fermentation vessel and will subside as the fermentation draws to an end. The length of fermentation is dependent on the health of the yeast, the original gravity of the wort, the temperature of the fermentation and the amount of yeast pitched, but typically takes anywhere from one week to three weeks for the majority of fermentation activity to complete.  A secondary fermentation is oftentimes conducted so that any remaining fermentable sugars can be converted to alcohol, and the beer can condition and allow the yeast to precipitate to the bottom of the fermenter in preparation for bottling or kegging.

 

Below is a photo of a top fermenting ale that was recently transferred to a secondary fermentation carboy.

Top Fermenting Ale - Beer

Top Fermenting Ale – Beer

Sparging

Sparging is a brewing process that involves passing heated water through the grain bed of a mash to extract sugars from the crushed grains and adjuncts. Sparging is typically conducted at approximately 167° F to 170° F; if the temperature exceeds 170° F, the brewer risks extracting excessive amounts of tannins from the grains. If the temperature is too low, then the sparge will be ineffective at liquefying the remaining converted sugars from the grains. While the sparge water passes from the hot liquor tank to the mash tun, or lauter tun, via a sparge arm, the extracted sugars and water are being drained from the base of the vessel and relocated to the boil kettle in preparation for to upcoming boil.

 

This mash is being sparged at 168° F, while the beer is being transferred from the false bottom at the base of the mash tun over to the boil kettle.

Sparging in the mash tun, while wort is transferred to the boil kettle.

Sparging in the mash tun, while wort is transferred to the boil kettle.

Pitching

Pitching or yeast pitching is the term used for when a brewer adds yeast to the cooled wort to begin the fermentation process. Yeast should be pitched to the wort as quickly as possible to diminish the possibility of wild yeast strains or bacteria taking control of the sweet wort before your selected yeast has the opportunity to. Additionally, your pitched yeast should be as close to the same temperature as the wort that you are adding it to in order to avoid shocking the yeast and to help the yeast acclimate as quickly as possible and lower yeast lag time. It is critical that your wort is in an appropriate temperature range for the yeast to be able to survive and thrive; for most ales that temperature range is between 65° and 80° F for pitching, but you should always consult your yeast’s packing for the specific temperature range of the variety you are using.

 

Cooled wort being aerated, just prior to having the yeast pitched.

Yeast Pitching and Aeration just prior to fermentation

Yeast pitching and aeration just prior to fermentation.

Saccharification

Saccharification in very basic terms is the conversion of starches to sugars. When it comes to all grain brewing, saccharification is a critical conversion process that occurs during mashing. As the mash tun’s temperature is increased to a range of 120° F to 158° F, the diastatic enzymes of the malted grains begin to activate and break the starches of the grains and adjuncts into sugars. The alpha amylase enzymes break apart complex starches into sugars that the beta amylase enzymes break apart even further into easy-to-ferment maltose sugar.

 

Precision is critical when it comes to the temperature of a mash and 10 degrees makes a massive difference. Beta amylase is more temperature dependent than alpha amylase, and when the temperature in the mash begins to rise above 158° F, the beta amylase is no longer capable of breaking apart the more complex sugar chains into maltose. So if your target mash temp is 152° F and you instead conduct your mash at 162° F, you will be left with a massive amount of unfermentable sugars in your finished beer, and it will have a fuller body and overly sweet finish.

Beta amylase thrives in a temperature range of 140° F to 150° F, so if your target mash temp was 152° F and you conducted your mash at 142° F, you would end up with a beer with a very thin body and dry finish due to a deficiency of unfermentable sugars. This is the reason why the typical mash saccharification rest temperature is in a range of 152° F to 154° F; it provides a good temperature compromise for both alpha amylase and beta amylase to carry out their required starch and sugar conversion processes.

Chill Haze

Chill haze is the cloudy or hazy appearance that a chilled beer gets when it is too high in residual proteins or tannins. For the most part, haze and turbidity are highly undesirable unless you are brewing a beer such as an American wheat, hefeweizen, or Belgian wit, where the style calls for a certain amount of haze. It is easier to try and avoid chill haze as opposed to trying to remove it from a beer.

 

Best practices for avoiding chill haze include properly controlling your mash out, sparging, lautering, and recirculation temperatures. Tannin extraction becomes a real issue when you exceed a temperature of 170° F in your mash tun, so always do your best to keep your sparge temp near 168° F for proper sugar extraction, but do not exceed it or else you will risk stripping too much tannin from the grain.

 

A consistent rolling boil and hot break are also important when it comes to reducing excess proteins. During the boil and hot break, proteins will merge together, becoming very dense and dropping out to the bottom of the kettle where they can be separated and not transferred to the fermenter. Perhaps one of the best and easiest ways to help avoid chill haze is to use an inexpensive fining such as whirlfloc. Whirlfloc is my personal favorite haze clearing fining; it is a blend of Irish moss and purified carrageenan. The Irish moss and carrageenan bind with the proteins and aid in precipitation. I will typically use one tablet per 5 to 15 gallons and add it at the last 15 minutes of the boil.

 

If you find yourself in the situation where when chilled your beer has haze and you have not yet bottled it, you can try one of the following methods to help clear chill haze. Extend your conditioning time and cold crash your beer to 34° F for a couple of weeks. This will aid in precipitation and help move suspended yeast and protein to the bottom of the vessel so that you can rack or transfer the clarified beer off the top of it. As a last ditch effort, you can use a beer clarifier such as gelatin. The gelatin should bind to the excess proteins, and drop some of the haze out of your beer.

 

Cold Crashing

Cold crashing or cold filtering is a common method used to clarify beer. When a beer is cold crashed, it is chilled down to approximately 35 F and left for several days to several weeks. During that time, yeast and other solids tend to clump together and fall to the bottom of the fermenter or holding tank. The clarified beer is then racked above the layer of sediment and potentially ran through a filter if additional clarification is desired. Cold crashing or filtering is not appropriate for some beer such as a hefeweizen or certain Belgian ales where a yeasty flavor or hazy beer is desired.

Ale

An ale is a beer that has been fermented using a top fermenting yeast. Ale yeasts are typically more resilient to warmer temperatures then their lager counterparts and are usually fermented at a temperature range of 65-75 F.  Since the yeast is more active at higher temperatures, an ale ferments much quicker then a lager.

 

Examples of ales include golden ales, pale ales, India pale ale, old ale, Belgian ale and barley wines.

 

Something to keep in mind when fermenting an ale is that ale yeast can ferment beer above a temperature of 75 F, but when doing so it will oftentimes create undesirable esters and off flavors.   Also, liquid ale yeast is vulnerable to high temperature, and it should be refrigerated to maintain its viability in transit and in storage. Due to the delicate nature of liquid yeast, I always create a yeast starter to verify its viability prior to pitching it in the cooled wort.

Alpha Acid

Alpha acid is one of the two soft resin acids that are present in hops. The alpha acids in hops are found in the resin glands of the flowers, and they are the primary source of the hop bitterness. In addition to their bittering properties, alpha acids also act as preservatives in beer. When heated in the brewing process, alpha acids are isomerized and form iso-alpha acids. The amount of time that the alpha acid is subjected to the boil determines the degree of isomerization that occurs and the amount of bitter flavoring that is  produced in the beer.

 

At a certain point, the boiling begins to have significantly diminished returns on the isomerization of the alpha acid and becomes ineffective for creating additional bitterness in the beer. Typically that occurs after 60 to 90 minutes of the hop being added to the heated wort. The isomerization process occurs when the wort is heated above approximately 175 F. The quantity of alpha acid present in a hop will determine the hops bittering potential. Alpha acid percentages vary dramatically between the different varieties of hops and are impacted by a multitude of outside factors such as storage packaging, age of the hop, storage temperature, oxidization, drying method, and growing conditions.

 

The most common alpha acids are humulone, adhumulone, cohumulone, posthumulone, and prehumulone.

 

Below is a list of commonly expected alpha acid levels for different hop varieties. These are not exact and are just intended for estimation purposes:

Ahtanum Hop, Alpha Acid 5.5-9%, Beta Acid 5-6.5%

Amarillo Hop, Alpha Acid 6-11%, Beta Acid 6-7%

Apollo Hop, Alpha Acid 15-21%, Beta Acid 5-8%

Australian Galaxy Hop, Alpha Acid 12-14%, Beta Acid 5.5%-6.5%

Australian Helga Hop, Alpha Acid 5-6.5%, Beta Acid 4-5%

Australian Pride of Ringwood Hop, Alpha Acid 6-8.5%, Beta Acid 4.5-5.5%

Austrailian Stella Hop, Alpha 14-16%, Beta Acid 4.5-5.5%

Australian Super Pride Hop, Alpha Acid 13-15%, Beta Acid 6-7%

Australian Sylva Hop, Alpha Acid 4.5-7%, Beta Acid 3-5%

Australian Topaz Hop, Alpha Acid 15-18%, Beta Acid 4-5%

Bravo Hop, Alpha Acid 14-17%, Beta Acid 3-4%

Calypso Hop, Alpha Acid 12-14%, Beta Acid 5-6%

Cascade Hop, Alpha Acid 4.5%-7%, Beta Acid 4.5-7%

Centennial Hop, Alpha Acid: 9.0-12.0%, Beta Acid 3.5%-4.5%

Chinook Hop, Alpha Acid 11-13%, Beta Acid 3%-4%

Citra Hop, Alpha Acid 11-13%, Beta Acid 3.5-4.5%

Cluster Hop, Alpha Acid 5.5-9%, Beta Acid 4.5%-6%

Columbus Hop, Alpha Acid 14-16%, Beta Acid 4.5%-5.5%

Crystal Hop, Alpha Acid 2-4.5%, Beta Acid 4.5%-6.5%

Czech Saaz Hop, Alpha Acid 3-4.5%, Beta Acid 3-4%

Delta Hop, Alpha Acid 5.5-7%, Beta Acid 5.5-7%

El Dorado Hop, Alpha Acid 13.5-16%, Beta Acid 7-8%

Falconer’s Flight Hop, Alpha Acid: 10-11%, Beta Acid 4.5-5.5%

French Strisselspalt Hop, Alpha Acid 3-5.5%, Beta Acid 3-6%

Galena Hop, Alpha Acid Pellets 12-14%, Beta Acid 7-9%

German Brewer’s Gold Hop, Alpha Acid 5-9%, Beta Acid 2.5-3.5%

German Hallertau Hop, Alpha Acid 3-5%, Beta Acid 4-5.5%

German Herkules Hop, Alpha Acid 12-17%, Beta Acid 4.5-5.5%

German Hersbrucker Hop, Alpha Acid 1.5-3.5%, Beta Acid 4.5-6%

German Magnum Hop, Alpha Acid 13-15%, Beta Acid 5-7%

German Merkur Hop, Alpha Acid 12-15%, Beta Acid 5-7.5%

German Northern Brewer Hop, Alpha Acid 8-10%, Beta Acid 5-6.5%

German Opal Hop, Alpha Acid 5-8%, Beta Acid 3-5.5%

German Perle Hop, Alpha Acid 6.5-9%, Beta Acid 5-6.5%

German Saphir Hop, Alpha Acid 2-4.5%, Beta Acid 2-4.5%

German Select Hop, Alpha Acid 3-6.5%, Beta Acid 3-4.5%

German Smaragd Hop, Alpha Acid 4-6%, Beta Acid 4-5%

German Spalt Hop, Alpha Acid 4-5.5%, Beta Acid 4-5%

German Tettnang Hop, Alpha Acid 3.5-5.5%, Beta Acid 5-6%

German Tradition Hop, Alpha Acid 5-7%, Beta Acid 4-5%

Glacier Hop, Alpha Acid 5.5%-6%, Beta Acid 6-8%

Horizon Hop, Alpha Acid 11-13%, Beta Acid 6.5-8.5%

Liberty Hop, Alpha Acid 3-5%, Beta Acid 3-4%

Millennium Hop, Alpha Acid 13.5-16%, Beta Acid 4.5-5.5%

Mosaic Hop, Alpha Acid: 11.5-13.5%, Beta Acid 3-4%

Mt. Hood Hop. Alpha Acid 4-7%, Beta Acid 5-7.5%

Mt. Rainier Hop, Alpha Acid 6-8%, Beta Acid 5-7.5%

Newport Hop, Alpha Acid 12-14%; Beta Acid 7-9.5%

New Zealand Green Bullet Hop, Alpha Acid 11-14%, Beta Acid 3-6%

New Zealand Hallertau Hop, Alpha Acid 6.5-8.5%, Beta Acid 3-4%

New Zealand Motueka Hop, Alpha Acid 6.5-7.5%, Beta Acid 5-6%

New Zealand Pacific Gem Hop, Alpha Acid 13-15%, Beta Acid 7-9%

New Zealand Pacific Hallertau Hop, Alpha Acid 5-6%, Beta Acid 3-4%

Nugget Hop, Alpha Acid 9-11%, Beta Acid 4-6%

Palisade Hop, Alpha Acid 5.5-9%, Beta Acid 6-8%

Perle Hop, Alpha Acid 7-9.5%, Beta Acid 4-5%

Santiam Hop, Alpha Acid 5.5-7%, Beta Acid 6-8.5%

Simcoe Hop, Alpha Acid 12-14%, Beta Acid 4-5%

Sterling Hop, Alpha Acid 6-9%, Beta Acid 4-6%

Styrian Aurora Hop, Alpha Acid 7-9%, Beta Acid 3-4.5%

Styrian Bobek Hop, Alpha Acid 3.5-7%, Beta Acid 4-6%

Styrian Celeja Hop, Alpha Acid 3-6%, Beta Acid 2-3.5%

Styrian Goldings Hop, Alpha Acid 4.5-6%, Beta Acid 2-3%

Summit Hop, Alpha Acid 17-19%, Beta Acid 4-5%

UK Admiral Hop, Alpha Acid 13-16%, Beta Acid 4.5-6.5%

UK Bramling Cross Hop, Alpha Acid 5-7%, Beta Acid 2-3.5%

UK First Gold Hop, Alpha Acid 6-9%, Beta Acid 3-4.5%

UK Fuggle Hop, Alpha Acid 3-5%, Beta Acid 5-6.5%

UK Kent Goldings Hop, Alpha Acid 4-5.5%, Beta Acid 2-4%

UK Minton Hop, Alpha Acid 5-7.5%, Beta Acid 3.5-4.5%

UK Northdown Hop, Alpha Acid 7.5-9.5%, Beta Acid 5-6%

UK Phoenix Hop, Alpha Acid 8-12%, Beta Acid 4-6%

UK Pilgrim Hop, Alpha Acid 9-13%, Beta Acid 4.5-6%

UK Progress Hop, Alpha Acid 5-7%, Beta Acid 2-3%

UK Target Hop, Alpha Acid 8-13%, Beta Acid 4.5-6%

UK Whitbread Goldings Hop, Alpha Acid 5-8%, Beta Acid 2-4%

US Brewer’s Gold Hop, Alpha Acid 8.5-9.5%, Beta Acid 3-5%

US Fuggle Hop, Alpha Acid 4.5-5%, Beta Acid 1-2%

US Goldings Hop, Alpha Acid 4-6%, Beta Acid 2-3%

US Northern Brewer Hop, Alpha Acid 8-10%, Beta Acid 3-5%

US Saaz Hop, Alpha Acid 3-4.5%, Beta Acid 3-6%

US Tettnang Hop, Alpha Acid 3.5-6%, Beta Acid 3-4%

Vanguard Hop, Alpha Acid 5-7%, Beta Acid 5-7%

Warrior Hop, Alpha Acid 14-16%, Beta Acid 4-5.5%

Willamette Hop, Alpha Acid 4-6%, Beta Acid 3-4%

Zythos Hop, Alpha Acid 10-11%, Beta Acid 5-6%

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