In this article we take a look at how using kveik yeasts can help you happily brew through the summer heat.
One of the biggest challenges when brewing over the summer months is controlling the temperature of your wort throughout the fermentation phase.
Ale yeasts will typically perform best between 18-25°C. But once the mercury starts heading north, a number of things can occur.
Firstly, it’s likely that your yeast will become more active. This can lead to quicker fermentation and the production of off-flavours as your yeast is producing more metabolic byproducts than it would normally. These metabolic byproducts can be present in the form of esters and fusel alcohols as well as acetaldehyde and diacetyl.
More worryingly, if your wort becomes too hot your yeast may become inactive or die, which can result in incomplete fermentation. This will likely leave you with a beer with higher final gravity and residual sweetness.
So, what to do when things start heating up outside?
A quick search of the internet will yield a litany of blog posts suggesting different ways to beat the heat. These usually involve converting old chest freezers, cranking the air conditioner or wrapping wet towels around your fermenter.
While these methods can help cool your brew, there is an easier way–brew with a kveik yeast.
About kveik yeasts
Originating in Norway, kveik yeast strains are unique in that they happily ferment at temperatures up to 40°C without imparting any off-flavours.
While this is great for people who don’t want to nurse their brews through periods of hot weather, there are other advantages of brewing with a kveik.
With a faster rate of fermentation, you can reduce the overall time it takes to brew a batch meaning you’ve got something to slake your thirst on those hot summer days.
Kveik yeasts are also known for the range of flavours and aromas they produce. Depending on the strain and fermentation conditions, kveik yeasts can produce citrusy, spicy, fruity and farmhouse-like aromas and flavours. This ability has seen them grow in popularity with craft brewers in recent years.
Kveiks are also versatile and are used to brew a range of beers. Here are some styles we suggest trying out with a kveik.
1. Norwegian Farmhouse Ale – This traditional style of beer was developed using Kveik yeast and owes much of its refreshing and fruity appeal to the strain.
2. Belgian Saison – Producing spicy and fruity esters, kveiks are a good choice for Saisons.
3. Wheat beer – again, kveiks are great for imparting the spicy and fruity esters typical of a good wheat beer.
4. American IPA – when brewing hop-forward IPAs, kveik yeasts can add a range of fruity flavours as well as citrus tang.
5. Stout – while kveik yeast is often associated with light, refreshing beers, it can contribute a range of unique flavours to stouts and other dark beers.
Brew it with Bluestone:
Bluestone currently has two kveik strains available to home brewers in handy 120ml live liquid yeast packs.
Bergen: Bergen is traditionally used in the production of Norwegian Farmhouse Ale, this strain is a fast fermenter with good attenuation, a light earthy spiciness, marked tartness and a unique ester profile of orange peel. Bergen will ferment a wort over a 21–37 ºC temperature range. At the cooler end of the range Bergen is clean; producing little to no esters and phenols. But builds a huge fruit ester profile as the temperature increases.
Oslo: Oslo is a great choice for a pseudo lager. It is a phenomenal wort attenuator producing super clean beers in just a few days. Keeping it hot is the key to getting your beer finished in just a few days without any off flavours.
