How does gluten free processing differ?

How does gluten free processing differ?

Barley is the mainstay of beer, and as such, most processing methods have been tailored to the benefit of this individual ingredient. Mill gap is set specifically based on kernel size and friability, via information that comes directly from the maltster. Hydration ratios are set based on the hydroscopic ability of the crushed barley grist, and even dedicated macerating pump impellers are implemented to move hydrated barley with minimal destruction. In the lauter, wedge-wire and laser cut false-bottoms are spaced ideally for crushed barley and its husks to remain while slowly collecting the valuable wort.

Unfortunately for GF brewers, barely is off the table. Product must be made using any number of alternative ingredients, but most pose unique challenges. From husk-less kernels to high gelatinization temperatures, standard brewing techniques must be modified for success. So where does brewing GF start to differ? Right from the beginning! The malting of GF ingredients requires a similar, yet modified approach from traditional barley brewing. If you need a simple solution, consider white sorghum or brown rice syrups from Briess Malt & Ingredients Co

Here sorghum is shown just before harvest. Although similar to Millet, sorghum offers a larger yield.

The first step in malting is steeping the grains in hot water. Temperature will vary by grain, but a difference of 10°F can have a large impact on enzyme development. During this phase, water is swelling the grain kernel to as much as 35-50% of its original size. For GF ingredients, you may see a large difference in steeping requirements between base varieties. Millet is smaller in size and will adsorb water quickly, however maize is much larger and can take significantly longer to hydrate. Each base variety must be treated independently to maximize its enzymatic potential. 

Germination too must be matched by grain variety, as tropical origin plants will germinate better at high temperatures, and the converse is true of cold-weather plants. The bio-activity of germination will generate heat, so it is important to “turn” the grain by moving it around. Millet is particularly susceptible to matting or molding if left stagnant, so aeration is also implemented.

Germinating rice will be kilned to stop the natural enzymatic process.

Kilning grain is by no means a straight forward process. Temperature, time, and surface area play a large roll, but each is modified based on the desired result. As a generality, larger kernel sizes will have more extended kilning periods. Potentially from 12 hours to two days. This is to slowly reduce the moisture content from 35-50% down to a stable 3-5%.  If you need more details on malting your own GF grains, click over to our friends at Gluten Free Home Brewing.

Once you have some acceptable malted grains to work with, you must continue to advocate on behalf of enzymatic activity. This means a traditional single infusion mash may not be appropriate for you, and instead a step or decoction may be implemented. Regardless, GF ingredients are weak in brewing friendly enzyme content. Often it is necessary (and always recommended) to add supplemental enzymes to aid in hydrolyzation and starch conversion.

Once germinated seed is kiln dried, the “culms” or rootlet pieces are culled from the malt, leaving just the kernel behind. Here, finished rice malt looks much like wheat kernels.

In barley brewing, a one-hour mash rest has represented the “standard operating procedure” for quite some time, even though modern modified malts may convert fully in as little as 20 minutes. Standardizing the process is paramount, regardless of the exact parameters. When using GF ingredients, it is important to consider extending the mash rest beyond the traditional hour. More time will allow the enzymes to convert more efficiently, increasing your overall yield.

One of the most efficient approaches to GF brewing is to use a ramping mash schedule and Novozymes supplements. Ceremix® Flex and Ondea® Pro can be added to the mash to enhance enzymatic activity and unlock more potential from chains of amylopectin. Initial rest should be made around 125°F, for a period of 20-30 minutes. The pH should be adjusted to 4.6-4.8 for maximum efficacy. Temperature should then be raised to about 144°F, the optimal temperature for natural beta amylase activity. Hold at this temp for about 45-75 minutes, depending on grist type and desired results. Before running to kettle, raise the temperature to 175°F to stop enzymatic activity and “lock-in” the wort composition you have created. 

Lautering is nearly identical to standard brewing practices, however the addition of rice hulls is desirable. Since the husk to kernel ratio of GF ingredients is not particularly favorable, save rice, is it important to create some levity in the lauter bed. Empty rice hulls create more entrained space between starchy grain fragments, allowing for better porosity and ultimately, more efficient wort collections. Sparge below 180°F to reduce risk of unpleasant tannin extraction.

A wide variety of starch-rich plants can be used for alcohol production. Each one poses unique challenges, however modern enzyme complexes have the potential to unlock untold potential.

After collecting the sweet wort, traditional brewing methods or new contemporary methods of fermentation can take over. A Gluten-Free beer alternative may make use of a simple strain of saccharomyces cerevisiae, while a Kombucha will use a more complex Symbiotic Culture of Bacteria & Yeast (SCOBY). The possibilities are open ended from here. You now have a sugar source from alternative, gluten-free ingredients!

Meet the Author

J.D. Angell

Meet the Author

J.D. Angell

After several years of providing hazardous materials training and maintenance for the world's largest brewing facility, JD began home brewing countless varieties of craft beer. Some early success and a detour with industrial scientific research engaged his interests in industrial equipment and complex science, while working at a liquid yeast supplier pointed him specifically towards enzymes. Currently heading Bircus Brewing Company in Ludlow, KY, JD blends contemporary flavors with traditional science and innovative techniques. With over a decade of operational brewing and independent contracting experience across 5 time zones, he has amassed a plethora of knowledge to share with fellow brewers.