Using Spent Grain Responsibly

One of the highest honors in the craft beer industry is the label of sustainable. Breweries stake their reputations on it, using locally grown ingredients to cut down on emission costs, building their brewpubs from recycled materials, reducing water usage, and attempting to throw away as little waste as possible.

Unfortunately, the very act of brewing beer results in one of the biggest waste products in the brewing industry – spent grain. About 85% of total brewery waste is made up of spent grains. However, over the generations, brewers have found some helpful and often fun ways to use spent grain.

Mashing is a step in the brewing process that combines malted barley and grains with hot water to convert complex starches into simple sugars that are more readily fermentable. After mashing is complete, this mixture will undergo sparging, the process of pouring hot water over the mashed grains to extract sugars and produce a sweet liquid called wort. The wort will go on in the process and become beer. The remaining grain bed of husks and other solids, now called spent grain, is no longer needed. The question for breweries then is how to dispose of it.

Of course the obvious question is why not just throw the spent grain away? For starters, there is a lot of it. For every gallon of beer produced, approximately 10 pounds of spent grain is left over. If a large brewery makes 10,000 gallons of beer on a given brewing day, that’s 100,000 pounds of spent grain. So, not only is it an utterly huge task, it is inherently wasteful and environmentally unfriendly to send 100,000 pounds of grain to the landfill every brew day. It is also expensive. The total added expense in the United States to waste management services, paid for by breweries, has been estimated by the Brewers Association to be over 43 million dollars per year!

Animal Feed

Most breweries donate the majority of their spent grain, approximately 80%, to farms for animal feed. This relationship has been a mutually beneficial one since brewers and farmers have lived side by side. In the early days of Anheuser-Busch, even Adolphus Busch, the man behind raising the then local brewery to a national powerhouse, invited farmers and ranchers to pick up spent grain from his St. Louis brewery.

Spent grain is most often donated to farmers, as long as they are willing to transport the grain themselves, cutting back on the massive cost of waste management services. Often farmers will install trailers at the brewery to be filled with spent grain on brew days. Then the farmer will pick up the spent grain and replace the full trailer with an empty one. Spent grain is an ideal animal feed because it is high in protein and fiber, but low in sugar, and has a bit of water, helping drought-prone areas to hydrate animals partially.

Brewery Vivant, a brewpub in Grand Rapids, Michigan, donates the majority of their 300,000 pounds a year of spent grain to a local cattle farm for feed. The brewery makes sustainability a major priority, and that includes their spent grain disposal. They have gone from “cow neutral,” feeding as many cows as they sell as beef in their restaurant to “cow positive,” feeding more cows than the equivalent amount of beef they sell.

Bear Republic Brewing Company in Healdsburg, California, annually donates the majority of their seven million pounds of spent grain to Oak Ridge Angus, a farm in Calistoga, California, that contributes beef from their cattle to needy families through a local assistance program.

Peter Kruger, Master Brewer at Bear Republic, told us, “One program that we do in conjunction with Cheryl LaFranchi and her Oak Ridge Angus is a program called ‘The Range to Table Program’ where we donate the grain to her, and she raises cattle that then are donated to local food banks. In 2014, [our two businesses] combined were able to donate 13 cattle which worked out to about 500 pounds of hamburger to the local food bank.”

Brewery Vivant’s Director of Operations, Brooks Twist, says that finding farms to take spent grain will usually be as simple as looking to contacts you’ve already made.

“Brewers are notorious for having great connections within our industry, so if you’re new and starting up, chances are you’ve already talked to a bunch of people about how to do this and how to do that, and everyone’s really helpful in sharing their connections and contacts, so it’s relatively simple to get set up with someone,” said Twist.

However, Kruger says, it’s not enough to know someone. They need to be reliable and understand the product they’ll be taking.

“Nothing is more of a pain in the neck than trying to deal with a bunch of spent grain that basically has turned and no one will take it at that point. It smells horrible and there’s not a lot of value to it,” said Kruger. “Because spent grain has such a finite window of use, it’s really important that the people you select are really reliable and are going to show up when they say they’re going to show up and take what they say they’re going to take.”


Composting is also an excellent method of reusing spent grain. Spent grain is classified as an organic green product that is rich in nitrogen content. Composted spent grain is used to fertilize fields and gardens both large scale and small. About 10% of Bear Republic’s spent grain is donated to a landscaping company in Cloverdale, California, who combine the spent grains and hops to form a highly efficient and sought after product.

“When you’re making compost, you want to have equal parts of what they call brown and green waste. The green is incredibly high in nitrogen and the brown is high in carbon. Malt is a very good brown type compost material. Fortunately, if you take hops, those are very high in nitrogen. Blended together in equal parts, that green hop material and malt make a really good feed stock for compost.

We work with a local company called DenBeste Landscape, and he makes a compost mix. Gallo [Family Vineyards] did a trial of 13 different composts and the compost that [DenBeste] makes provided the best benefit to them for their landscaping needs,” said Kruger.

Urban Alternatives

Animal feed is an excellent disposal method for breweries located in rural communities or mid-sized cities, but in major urban centers, this is seldom an option. Farms are either non-existent or far away, or breweries are located in buildings that don’t have easy access for a large trailer. In these situations, bigger city waste management facilities do offer composting, as do private companies, but that can also be quite expensive. Because of these barriers, urban breweries must come up with other ways to dispose of spent grain responsibly.

Although many waste management companies are unable to process the large amounts of spent grain that are donated to farms or for composting, their existence gives urban breweries alternatives to the landfill, and shows an awareness and an interest from other urban businesses in helping breweries succeed.
Breweries are the first ones to use their spent grain in their restaurants. Brewery Vivant uses spent grain in some of their recipes, and another Grand Rapids area brewery, TripelRoot, makes cookies with spent grain.

Bakeries have embraced spent grain as an ingredient in their products. Hewn, a bakery in Evanston, Illinois, just north of Chicago, folds spent grain from area breweries The Peckish Pig and Sketchbook Brewing Company into their bread dough to make Spent Grain bread.

Doggie Beer Bones in San Diego, California, makes dog treats from spent grain, including “Stone Bones” from Stone Brewing Company spent grain. Similarly, BareBites in Frederick, Maryland, makes “Brew-yahs,” a spent grain treat for dogs.

ReGrained in San Francisco has teamed up with 21st Amendment Brewery, Magnolia Brewery, and Triple Voodoo to make granola bars from spent grain and other locally sourced ingredients. While attending UCLA, ReGrained founders Dan Kurzrock and Jordan Schwartz were home brewing when they realized that they were throwing away a possibly quality food product.

“I’d make this big batch of what looked and smelled like oatmeal, and I’d continue making my beer, and then I’d have to take this big tub of stuff that looked like food and have to throw it away. I grew up in a very much ‘waste not, want not’ household in Northern California, and that wasn’t gonna cut it,” said Kurzrock.

They made the bars and sold them around campus before realizing they could go bigger. Originally seeing a chance to create a brewery and bakery in one, brewing quality beer and then making quality products with spent grain, they began focusing more on the bakery side of things when more urban breweries began opening.

Kurzrock does not want ReGrained to become known as just a “granola bar company.” They have plans to create more products from spent grain using spent grain flour, a flour that can be used similarly to wheat flour, with less sugar than white flour.

ReGrained is also working on more products and on equipment that will help breweries dry their spent grain quickly. Spent grain has a short shelf life – if left wet and sitting, it will begin to mold and produce the ozone killing chemical methane. If dried, it has a greatly extended shelf life, and can be packaged and shipped for later use.


Breweries are also turning to spent grain for their energy needs. Bear Republic currently uses an anaerobic digester to convert organic materials at their brewery into methane to cut down energy costs. The system, built by Cambrian Innovation, is the “first bioelectrically enhanced wastewater pretreatment plant.” According to Bear Republic’s website, in addition to creating high quality methane, this system, called EcoVolt, provides 25% of Bear Republic’s hot water heating and close to 50 percent of their electrical needs. Over the next few months, they plan to implement a mash filter press that will squeeze the water from their spent grain to be used as a fuel source for the EcoVolt.

“We would continue to give away the grain but that liquid is squeezed out and that liquid would run through our anaerobic reactors and get turned into methane. If we can squeeze that grain to remove that liquid, that is excellent feed stuff for the bacteria that make the methane, and it also will allow us to ship much lighter grain and hopefully get more in each truck load to reduce the carbon impact of that truck trip,” said Kruger.

Alaskan Brewing Company in Juneau uses their spent grain as a power source. In Alaska, there are no cows, and it can get expensive for breweries to dry and ship spent grains to the lower 48. They were the first brewery in the United States to install a mash filter press to squeeze the moisture from their spent grain, not to run the water through an anaerobic system like Bear Republic, but to power their one-of-a-kind steam boiler solely by spent grain. The result is lower energy costs, fantastic sustainability, and as they say “Beer powered Beer.”

Spent grain is an inevitable byproduct of making beer, but it is also a versatile, valuable and low-cost raw material. Environmental and economic costs related to its responsible disposal have prompted various solutions. What other innovative uses for spent grain are awaiting imaginative brewers and entrepreneurs?