Gluten Free Brewing

I've had multiple inquiries from people about brewing gluten free beers for family members or friends (which is very cool!). I'll try to keep this as concise as I can, though I'm expecting it will be lengthy.

*Disclaimer - I would like to keep the gluten reduced (clarity ferm) debate out of this thread, but I do think that I need to state that the science involved in testing gluten reduced beers and the effects on people with celiacs is very hazy at best. My focus here will be on 100% gluten free beer*

Extract
Brewing a GF extract beer is really similar to using LME. You can use Sorghum Syrup (available at most LHBS) or brown rice syrup, or both. Many people also add various types of honey (particularly buckwheat honey) or Belgian Candi syrups for color and flavor. It is also common to add maltodextrin to build a bit of body, however, expect a very thin finished product with very little (if any) head retention. You will definitely need yeast nutrient, because these GF ingredients are severely lacking. Here's a link to a very common recipe:

https://ghostfishbrewing.com/2014/01/23/gfhomebrewing-grapefruit-ipa/

I personally hate the tart, metallic taste of sorghum. If you've ever had a commercially made GF beer, you probably know what I'm talking about. However, it is the cheapest and easiest option and there are ways to mask the flavor.

All Grain
This is where you can really start to make some delicious beer and pass it off as a regular brew. However, it requires some extra work, money, and longer brew days than barley brewing.

The Grains:

Millet - This is really the base malt of choice imo. It is the most similar to barely, offering a clean sweetness. It will offer some body, but nowhere near that of barely. There are various roasts to choose from, allowing you to brew many styles. The dark malts are the biggest challenge. Go to light and your porter/stout will be overly sweet and malty closer to a brown ale. Step a little over the line and go to dark and you will have a acrid, bitter mess. I'm still trying to find what I consider to be the right balance.

Rice - Another base & specialty malt option. If used in high quantities, your beer will definitely have a more cidery feel to it. But, it does produce a very clean flavor. I like to use it in lighter styles like witbiers, saisons, etc., but never go more than 50%.

Buckwheat - Said to add body and head retention due to the higher beta-glucan content. IMO, the difference isn't huge, but I'm still experimenting. Some also say it contributes little to no flavor, while others say it has an 'off' flavor. I've been brewing brews with and without buckwheat lately to really get a stronger sense, but the jury is still out for me.

Lentils - I have not used these at all. I've had beers made with them, but did not like them at all. Here is a common partial mash recipe if you're interested:
https://www.groundbreakerbrewing.com/news/2017/6/16/ground-breaker-brewing-releases-gluten-free-
homebrew-recipe

Chestnuts - Another ingredient I have not used...no help there.

Oats - Good for beta-glucan, but the high fat content really kills head retention and lacing ime. The low protein content in the other GF grains can't combat the fat. However, oats do add a nice flavor and mouthfeel. Also note that some people have a reaction to oats due to the avenin content, even if the oats are GF.

Teff & Quinoa - Both have a higher protein content and teff in particular has lower fat. Said to help with head retention and mouthfeel. Again, jury is still out. At this point I will substitute Teff for oats in my recipes, but I'm still not confident enough to take a strong stance on it.

There are other GF options out there like Amaranth, corn, sunflower seeds, etc, but I have not used them at this point.

BTW - these malted grains are friggin expensive and only available online (or you can malt them yourself).
https://www.glutenfreehomebrewing.com/STORECategory/131/Malt-Grain.html
https://www.boulderfermentationsupply.com/shop/colorado-malted-gluten-free-grains/

Yeast Nutrient - use it. These grains do not have the nutritional content of barley/wheat/rye.

The Process

First of all, if you're going to brew a GF beer you need to be careful of all cross contamination. Make sure your ingredients are gluten free, are kept away from gluten containing ingredients and equipment. Even some simple barley dust in the air, or a contaminated scoop can cause problems for people. Your mill is the biggest problem, but you can buy pre-ground malts.

The biggest issue with all grain GF brewing is that the grains require a very high gelatinization temperature (like 168-185). However, mashing that high destroys the enzymes in your grains. There a couple of ways to deal with this. One is to mash in low, decant off the liquid to preserve the enzymes, raise temp to gelatinize the starches, lower the temp to safe saccharification temps and add the decanted liquid back in. I'm too lazy for that, so I use commercial enzymes and do a gelatinization rest at 175ish for 20-30 minutes and then drop to saccharification temps for 60-90 minutes.

Beta-Glucan and protein rests are an option obviously. A BG rest can really help your efficiency if you have a high amount of buckwheat or oats. I sometimes employ these rests, but the effect on the resulting beer is still unclear.

Enzymes
Termamyl - This stuff is really the workhorse alpha amylase that is TEMP STABLE enough to liquify the starches. I add it at the start of the mash and let it work it's magic.

SEBAmyl L, Diastase, AMG-300L - common enzymes to use at saccharification temps. I add them once I drop the temperature into a safe range (145-155ish). I've learned that SEBAmyl does not do well at converting rice FWIW.

Some people advocate a single infusion mash at 163, adding both enzymes and mashing for up to 2 hours. I haven't had great experience with this because I don't find that I get the same efficiency or conversion (and again these grains are $$$), but many people do it (including dedicated GF breweries that find it too difficult to change temps on such large batches).

Ph - the enzymes we're using have different ideal ph ranges for optimal conversion FWIW.

Gear - I purchased a grainfather because of challenges involved in brewing gluten free. It allows me to adjust temperatures easily and recirculate which really helps with efficiency and producing a clear wort. One thing is that GF grains are much smaller than barely, so you will have to adjust for that. I use a BIAB around my grain basket to keep the grains from slipping into the kettle. You will also need rice hulls or rice malt in your grist to avoid a stuck mash/sparge. Buckwheat can especially really gum up your mash and absorb a lot of water. If you do BIAB, expect a cloudy wort and I greatly recommend sparging to get a little more out of these expensive grains.

After the mash things are pretty straight forward. Number 1, is your yeast must be GF as well. The easiest route is to use dry yeast, but you can also plate and build it up on a GF medium, but I have not gotten this far yet. The biggest issue is trying to dial in attenuation. GF wort is comprised of more simple sugars and less dextrins. This usually results in a higher attenuated product, which can be very thin and/or dry. I'm constantly adjusting my enzyme amounts, mash temps, pitching rates, etc, to try to dial in my FG, but it's still a work in progress. There are just so many variables in play.

Here's an example of one of my beers...
https://www.brewersfriend.com/homebrew/recipe/view/740788/pliny-gluten-free

Lots of recipes:
https://www.glutenfreehomebrewing.com/recipes/findrecipe.php

Other tutorials (there are many ways to skin this cat)
https://www.glutenfreehomebrewing.com/tutorials.php

Ok, I think I'm done for now. If I think of something, I'll add it. Feel free to ask questions or provide input that may help with some of these issues. Some of you have so much experience with brewing/science, so I'd love to hear your thoughts.

 

Nah, i don't think I'm really an authority. I'm just sharing what I've learned.

I'm a member of the Zero Tolerance Homebrew club (almost 500 members) and there are far more experienced and knowledgeable people in there. Joe Morris just had an article in Zymurgy and Robert Keifer has presented at home brew con and has written articles.

 

Ah, I forgot to add partial mash. I have not used brown rice syrup, but some of my earlier brews were partial mash with sorghum syrup, buckwheat honey and I steeped some Bob's Red Mill tasty cereal (there are a few varieties). You could also use kasha or oats. All of it is at the supermarket. It definitely adds some flavor and boosts body a bit....but I still hate that sorghum. It's worth a shot though!

I never really took the time to dial in any extract or partial mash recipes because I wanted to jump to AG so bad. However, I had zero brewing experience. I think I could do a much better job now.

 

That recipe looks pretty nice. The only thing that stands out is the mash regime. There's no talk of enzymes and the rests are short. UsuallyUyou wouldwsee thatt163° rest for up to 2 hours. I would think the conversion would be pretty weak (but it is a pretty large grain bill for that OG). I'd wonder if it would pass a starch test though. You would also want 10-15% rice hulls too!

I don't hate on brown rice syrup, just never went down that path.

I think Belgian styles are a perfect choice for GF brewing. The phenolics, lighter body, Candi syrups, etc all work very well. I'm still enjoying this and will brew it again ..

https://www.brewersfriend.com/homebrew/recipe/view/743583/dubbel-gluten-free

 

That's awesome! If this helps brewers help a family member or friend, or just allows them to nerd out and tackle a new challenge, then it's all good. Cheers!