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What is Sour beer?

What is Sour beer?

When we released Pulp Fusion Passionfruit Sour in the summer of 2020/21, we had no idea how it would be received. We assumed that a lot of people would have never heard of a Sour beer, let alone tried one.

The gluten free community went nuts for it – even those who don't need to avoid gluten jumped on board! It actually won a silver medal at the Queensland Beer Awards in the Berliner-Style Weisse class (up against all beers) which we were super excited about.

“As a gluten free consumer, Id heard about all the sour beers being brewed in the ‘barley-beer’ world, and was keen to taste one to see what the fuss was all about, said CEO and Founder Richard Jeffares. 

Outside of the gluten free beer world, drinkers have had access to a huge range of sours since the style exploded at the end of the 2010s – now it's time for those who avoid gluten to get in on the fun! 

We were keen to brew more sours (and our customers were asking us too!), so we put out a Raspberry Berliner Weisse in March and then we had no hesitation in backing it up with Margarita Sour, a lime gose style beer, in time for summer 2021/22. 

Margarita Sour

Brewed for clean, crisp sour notes with zesty lime aromatics and mineral flavours, Margarita Sour is inspired by the hottest cocktail of 2022; the classic, refreshing Margarita. 

“All of our sours have shown the diversity of what we’re able to do with gluten free grains,” says TWØBAYS head brewer Kristian Martin. 

"They are ‘kettle sours’ [more on that later] brewed with a live lactic culture, which creates an approachable sourness, as well as providing a lot of fruity aromatics – such as apple and lemon.  

“We used real passion fruit pulp and real lime zest and we’re really pleased with the big fruitful flavours in the beers – it’s great to be able to offer the gluten free community a style of beer that they would not have otherwise had a chance to try.” 

With lower alcohol content (Pulp Fusion 3.5% abv and Margarita Sour 3.8% abv), sours are perfectly sessionable on any day – and especially refreshing on a warm one. They are also the closest beer style to cider, for those that aren’t that excited about beer 

So, how do you make a beer go sour? 

Intentionally acidic, tart or sour in flavour, sour beers are traditionally made by allowing wild yeast strains or bacteria into the brew trough barrels or during the cooling off the wort (beer before fermenting). 

While this method is still commonplace, the use of wild yeast can cause the beer to take months to ferment (and it is not always gluten free), but now brewers can use a method called 'Kettle Souring' to create a similar flavour profile in a more controlled environment and a shorter time period.  

Instead of a traditional mash, kettle sours undergo a “sour mash.” Basically, instead of boiling the beer-to-be and then cooling it to ready it for yeast, the liquid is boiled, cooled, and dosed with a ‘magic’ ingredient. 

Mashing is the process of combining a mix of grains – in this instance Vienna Millet Malt and Biscuit Rice Malt with water and then heating the mixture. Mashing allows the enzymes in the malt to break down the starch in the grain into sugars to create a malty liquid called wort, which is then combined with yeast (and beautiful hops) to ferment and become beer. 

The magic ingredient that turns an ordinary mash into a sour mash? Lactobacillus! 

This wort mixture then chills (literally) for a few days in the “kettle” while the liquid sours. Once the desired level of tartness is achieved, the normal brewing process is resumed. Boil; add hops; cool wort; add yeast and let ferment. 

“Kettle” refers to the brew kettle, meaning the beer is soured in a stainless steel mash tun and fermented in a similar tank. This denotes the key difference between kettle sours and traditional sours: steel over barrel. 

Souring in a steel “kettle” is faster and easier than the traditional sour beer method. The latter often involves aging in wood with a mix of microbes, and, most of all, time. Traditional sours can take several months or even years to create, while a kettle sour can be turned around in a matter of days. It’s a great way for busy brewers to get their tart on. 

What's the difference between the different sour beer styles? 

Here’s a brief rundown on some of the most well known sour beer styles.. 

  • Gose (pronounced Goes-Uh): a top fermenting beer which originated in Germany, which, in addition to its sourness is characterised by the use of salt and to provide its distinctive flavour.  
  • Berliner Weisse: a tarty, cloudy German beer, typically around 3% abv and often served with a fruity syrup. It’s a good entry level point into the world of Sours. 
  • Flanders Red Ale: sometimes referred to as ‘Flemish reds’, these Belgian beers with a distinctive red hue are fermented with brewers yeast and aged in oak barrels until mature. 
  • Oud Bruin: another Belgian beer (originating in the Flemmish region), which is infused with cultured yeasts and is similar to Flanders Red Ale but is darker in colour, with brown ale used as its ‘base’ beer. 
  • Lambic: these barrel aged Belgian beers are spontaneously fermented using naturally occurring wild yeast. Derivatives include Gueze, Kriek and Framboise. 

Our Margarita Sour is a Gose styled beer, and Pulp Fusion was a Berliner Weisse styled beer. As you can see, there are still some different styles that we can brew in the future which is very exciting! 

If you’re excited to try our Margarita Sour, here's what other people are saying: 

Was surprised how good the margarita sour beer was, probably the best gluten free beer I have tried and now makes everything good as I don’t miss stone and wood anymore. Michael C. 

I must admit that was the most excited about the Margarita Sour release as the “Gluten Glams” have been enjoying this specialty brew for quite some time. One is not enough. Or two (drink responsibly) but the more you drink the better this gets!! Catherine B. 

Goes down very very easily - incredibly refreshing in warm weather, even for non beer drinkers. Love the innovative flavour profile. Sam T. 

The first flavour I get is a grainy coriander seed flavour. A little earthy (maybe the salt) but no malt at all. It quickly disappears to a refreshing and very well balanced lime flavour. Not a fake lime flavour but a freshly squeezed lime flavour. The tongue does slightly wiggle as the incredibly balanced sourness finishes up cleaning the palette and asking you to drink some more. Which I did. 

It's light this beer. But it's supposed to be. It doesn't sit heavy and it's definitely an easy drinker, medium strength and quite smashable. For someone that isn't a fan of sours I don't mind this at all and I'd be happy to buy a couple on a hot day at a restaurant or even a music festival. Grant C. 

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