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Low ABV brewing and Dextrin malts

The pursuit of a full bodied low ABV beer.

As I continue down this path we call life, I like many, are often thrown curve balls that change the way we live life and effects our every day routines. One of those recent curveballs for me has been my inability to process alcohol as effectively as I did while in my youth. As a homebrewer and someone who loves the art of brewing in general this kind of, well, sucks. So about a 2 years ago I started on the journey of lower ABV beers and how I could improve on what's available in the “ZERO” to “Less than 1.5% abv” beers on the market currently, and stay within my wheelhouse and what I'm capable of achieving as a homebrewer. I started this endeavor by asking myself these two simple but ridiculously loaded questions.

Can a home brewer create a full bodied low ABV beer, say in the < 2% ABV range, using somewhat advanced brewing techniques, water chemistry, and selected ingredients?

Secondarily, can two similarly brewed low ABV beers, brewed with slightly different grain bills, have distinctly different amounts of perceived body by adding more dextrin rich malts to a high temperature mash?

So after many mediocre attempts, and learning along the way I believe I've come up with a fairly decent method to brewing a low ABV beer that can easily compete with most of today's commercially available offers in the 1-2% realm.

So where do we start? I think with many beer styles the grain bill is an important starting point, but in this style of brewing it's a secondary or even tertiary thought, as mash temperatures, yeast selection and water chemistry play a much larger role in the making of low ABV beer than the grain bill itself. That's not to say the recipe you develop isn't important and won't contribute to the overall character of the beer, it's just not as important in the process as staying within certain guidelines to achieve the end product you desire from an alcohol position.

What are these guidelines you speak of and how important is it to stay within the boundaries of these guidelines? Well over the time that I've been brewing lower ABV beers I've come to the conclusion that to brew successfully you must keep mash temperatures between 179-180F and pH at a fairly consistent throughout the whole brewing process, and I'll explain why temperature is so important. I experimented with mash temperatures in the range of 162F-180F and found that beers brewed in the lower range contained too much in the way of fermentable sugars, and not enough in way of long chain non-fermentable sugars that contribute to the perceived body but are not fermentable by my choice of Maltose negative yeast strains. Why is this important? Well since we're looking at creating lower alcohol levels and increasing the perception of body, we have to remember that with standard temperature mashes your base grain amounts and mash temps dictate the amount alcohol you'll have in the beer. Whereas with maltose/maltotriose extraction and high temperature mashes you're preventing most of the beta amalyse enzymatic conversion from occurring like when you perform a Sacc rest, thus allowing alpha amalyse conversion of starches through hydrolysis at higher temperatures producing primarily long chain dextrins and low amounts of fermentable sugars. In low ABV beers you're looking to create more Maltose and Maltotriose than glucose, fructose, and sucrose and make the wort inedible for your preferred maltose-negative yeast. Maltose-negative yeast is important as as I understand it because these yeasts cannot process Maltose and Maltotriose resulting in beers high in Maltose and Maltotriose post-fermentation with little in the way of produced alcohol. Setting up for your recipe using this style of brewing is pretty simple, I shoot for a starting gravity in the 1.018-1.025 with base grain taking up 25-30% of the grain bill. One important aspect to remember when building your recipe is that efficiency should be set to 50% as this style of brewing will only give you a range of 45-55% efficiency, especially at the temperatures we're mashing at. With base grains being limited in weight due to our desire to keep alcohol low it's a waste of resources to include more base grain than 30-40%. So how do we balance a beer that's obviously going to lack body and mouthfeel without increasing the alcohol levels? Lots of dextrin malts, oats, wheat, and even some crystal malts. My go to recipe currently is as follows; 31.4% Pilsner malt

21% Carapils

21% Chit malt

10.6% Oats 10.6% Flaked Wheat

5.3% Carafoam

Mash;

82C for 30 min

85C Mashout

Hops

56g Azacca in Mash

28g Mosaic cryo hopstand for 15 min at 52C

28g Citra cryo hopstand for 15 min at 52C

14g Nelson Sauvin Dryhop 3 days

14g Amarillo Dryhop 3 days

Yeast;

Escarpment Labs Hydra (Maltose negative with a 65% apparent attenuation capability) Alternative yeast; Lalbrew London Lalbrew Windsor

What about water chemistry? Balance is key, strike water, sparge water, and the boil should all remain in the 5.2-5.3 pH range as possible, I prefer a higher Chloride water profile for brewing low ABV beers. Brewing water high in chlorides improves body, and perceived mouthfeel, but it can also create a beer that's unbalanced if the malty backbone gets too prevalent. And this is where hops come in to play.

So hop additions and low ABV beers.... No boil hops is my go to here. I'll mash hop, whirlpool and dryhop. Most beers in the lower ABV realm benefit from a hop schedule that provides a decent bitterness in the 10-15 IBU level. Although I have brewed a few English style lower ABV beers that were in the 20-25 IBU range without being overbearing, with enough crystal malt to balance the bitterness you can be very successful at those levels.

So lets do a social experiment and see if there's a discernible difference between two similar beers but with one of the two containing a higher concentration of dextrin malts. Lets see where the differences lie and how the two beer compare to eachother.

Insert Peer Data Here

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