Get Spent: How Breweries and Homebrewers Are Finding New Uses for Spent Grain

Comments are closed.



By Alex Bach


Anyone who’s ever witnessed a beer enthusiast shamelessly sucking down the last possible drops of nectar from their glass knows beer drinkers are not inherently wasteful people; thankfully, neither are many of the breweries that create these tasty libations. To eliminate wastefulness, brewers are coming up with great ways to cut down on their carbon footprint or contribute to a model of sustainability. Brooklyn Brewery and New Belgium Brewing both utilize wind energy to power their operations. Full Sail Brewing out of Hood River, Oregon brews with 50% less water than standard breweries. California’s Sierra Nevada is 100% solar-powered, with Stone hot on their heels. So it should come as no surprise to learn that many of them find new uses for their spent grain as well.


What Are Spent Grains?


Mashing is the process of extracting fermentable sugars via hot water from dry starches (grains) to create the liquid wort, which, when fermented, becomes beer. Once the sugars are extracted, the grains play no additional role in the brewing process, and brewers are left with a bulky byproduct sitting in their kettles.

Let’s look at the numbers: Ryan O’Doherty of Half Acre estimates that each batch of beer utilizes anywhere from 1,400 to 2,400 lbs of grain per batch, depending on the style – 2,250 to 3,840 lbs of soaking wet grain after the mash-out. At 16-20 batches per week, that amounts to about 50,000 lbs of spent grain each week. Thankfully, they have a system in place to recycle that amount of still-viable product.

A 3-inch pipe takes the spent grain while it’s still hydrated through 100 feet of the brewery floor, climbing 15 feet to a conduit in the side where it is pumped into an empty trailer. Once a week, when the trailer is full, O’Doherty places a call to a local farmer they’ve partnered with and he drives up with an empty trailer, swaps it out, and brings the spent grains back to his farm to feed his cattle and pigs. The process repeats every week.




What’s fantastic about Half Acre’s model is that it is not an unusual arrangement. O’Doherty, who had previously worked at Yazoo Brewing out of Nashville, had a similar arrangement with a local farmer out there who used the spent grain to feed his pigs. Those pigs would then become part of Nashville’s famed BBQ scene, and sometimes – when the brewers were lucky – they would receive samples of pulled pork and ribs “fattened” off their own grains.

Yazoo and the farmer who receives their spent grain are not the only one to make bucolic pairings. Great Lakes Brewing out of Cleveland, Ohio donates their spent grains to local farmers as well as uses it for composting. Piney River Brewing goes one step further, housing their brewery on-site at their 80-acre farm nestled in the Missouri Ozarks – which means their cattle get the freshest grains, and they don’t have to worry about storing and shipping.




One Brewer’s Trash…


Some brewers, such as Marz Community Brewing, contribute to farming in a wholly different fashion by donating their spent grains to local composting facilities. Nancy Klehm, of Social Ecologies and Spontaneous Vegetation, is a compost professional who helps distribute compost to a variety of urban farms and gardens from Garfield Park to North Lawndale.

“Grains are a good composting agent for the moisture they retain, and the fact that they attract beneficial bacteria to help break down the grain at a faster rate,” Klehm said. Grains are not without their caveat, however. “Compost is fermentation at lower temperatures,” Klehm said, and just like any fermentation, certain conditions need to be met. Compost, much like yeast, needs proper aeration and acidity levels in order to break down properly.

While brewing grains are rich in nutrients, they need to be spread out and mixed with carbon-based fillers like sawdust, cardboard, and gypsum in order to let the compost breathe. Similarly, certain grain bills, such as those of sour beers, are very acidic and have to be blended in order to balance out the soil.

Just like O’Doherty had talked about with farmer reciprocity, it would be great to see some of those participating farms turn over some of their produce back to the breweries: homegrown berries for a sour, fresh coriander for a gose, or compost-grown hops for a local wet-hopped pale ale.


Surf & Turf


Though considerably less appetizing than the aforementioned pulled pork, these environmentally conscious uses of spent grain are another option for breweries looking to go green with their grain. Several breweries, like Avery Brewing out of Boulder, CO or Bear Republic out of Healdsburg, CA, have begun experimenting with their wastewater as a means of water treatment, filching out nitrogen runoff. Lakefront Brewery out of Milwaukee, Wisconsin was even awarded a Green Tier award from the state for their various commitments to sustainability, which includes converting 15,000 lbs of spent grain per week into super-soil, somewhere between compost and fertilizer.






Baked goods are another fantastic option for the used-but-not-useless carbohydrates. Many breweries pair with a local bakery to turn their spent grains into breads, which can then be served in brewery taprooms as a supplemental treat. Hewn Bakery in Chicago uses both a brew and its spent grains to fashion delicious breads. Baked goods aren’t just for human consumption, either.

Doggie Beer Bones out of San Diego uses spent grain from local breweries like Green Flash, Societe Brewing Co., and Stone to create a line of dog treats. Their treats are made with barley, peanut butter, barley flour, eggs, and water, but contain no wheat, soy, corn, or hops, which are poisonous to dogs. (This means they have to be critical of the ingredients they use, since not every batch of spent grains will work.)


Homebrewer Options


While the above solutions are done at a much larger scale than any homebrewer could ever achieve (through definition alone), many of those options are still available. Many breweries allow homebrewers to bring in their spent grains and add them to their farm contributions. Composting is not ideal for urban homebrewers, as the sweetness of the grain makes it veritable catnip for rats and mice.

Baked options are probably the most popular choice, with homemade breads being the most common fare; when making breads, many recommend drying and grinding the grains to break down the hulls (especially if using grain bills with rice hulls). There are also numerous recipes online for creating your own granola or doggie treats. Most recipes for dog biscuits consist of variations on the following:

  • 1-2 cups of spent grain*
  • 1/4 cup flour
  • 1/4 cup peanut butter or molasses (for taste)
  • 1 egg (to bind it together)
  • Mix ingredients together in a bowl and form into biscuits
  • Place biscuits on wax paper and bake in the oven at 350ºF for about 20 minutes

*Remember not to use grains that have been exposed to hops.


I’m Spent


The territory of brewing comes with a lot of waste products; fortunately, we don’t have to be wasteful with all of them. Finding new uses for spent grain is a great way to invest in sustainability and one that might lead to some delicious returns on your investment.


– Alex Bach earned his MA in Fiction Writing from Johns Hopkins University and has been publishing in the US and UK. When not writing he can be found behind the brew kettle trying to hone his home brewing skills.



February 2016
« Jan   Mar »


Need help with your subscription?

What to contribute to the magazine?

Subscribe to our Newsletter