The scene is familiar to many adults in Minnesota: at the end of the week, you sit down with friends, family or a partner, ideally somewhere outside, and have a beer together, catching up and enjoying each other’s company. In a state with so many breweries, it’s only natural that we enjoy the variety of sours, pilsners, lagers and ales available to us. However, what if you knew your beer was in conflict with your personal sustainability goals? That’s right—the brewing process creates a fair amount of “spent grain,” which is difficult to manage. Spent grain removal requires a lot of coordination between farmers and brewers, which can take the form of time spent, miles driven and unpredictability. But it doesn’t have to.
We have been working with partners to find sustainable uses and practices for spent grain. As part of this project, we’ve been learning more about the brewing process, and some of the options for solutions that are used around the state. We visited Lupulin Brewing to hear more about their process (and try some of their beer!), then went down the road to Iron Shoe Farm, the farm that has been helping them find a solution.
The brewing process starts with grain. The grain is crushed and combined with water, which makes a “mash.” The sugars from the grain are extracted into the mash, which helps the beer begin to develop. That mixture is transferred into a kettle, where it will continue its journey to becoming a beer. However, the grain is left behind in a piece of equipment called the “lauter tun,” having been “spent” during the process. At the end, there are two products: beer and the grain we began with. However, the gain has gotten wet and between three and four times heavier than it was to start, so the question becomes what to do with it. At Lupulin, they’ll produce between 6,000 and 8,000 barrels of beer this year, which means they produce about 30,000 pounds of spent grain each week. Though the spent grain lacks the sugars necessary for reuse in brewing, it still has plenty of nutrients—which animals are perfectly happy to eat. That’s where Iron Shoe comes in. After Lupulin has removed the spent grain from the lauter tun, Iron Shoe loads it up and takes it to their farm, where anxiously awaiting pigs, cattle, chickens and even a horse eat it.
When talking to Ben at Lupulin and Carla at Iron Shoe, we were struck by their partnership. Or, more accurately, their relationship. The two businesses came together because they have common goals. “We all love beer, and it’s a shame that there’s this byproduct that goes into landfills,” said Ben. By working together, they are able to grow their own business and support another small business so both thrive. “It’s not a partnership, but a relationship…it builds community, especially being fairly local. We can really invest in each other’s markets. It’s fun to see your neighbor succeed.” And, importantly, they prevent the spent grain from going to waste.
That’s not to say that the system that Lupulin and Iron Shoe use is perfect. For example, Lupulin has a forklift, so they can easily lift the heavy grain onto the back of Carla’s truck. However, the farm doesn’t have that equipment, so they must hand-shovel the grain off the truck. Another challenge both face is that Carla’s animals prefer the grain used to brew light beer! While the hops and alcohol are added at a later stage in the brewing process, making the spent grain safe for animal consumption, the types of grain used at the beginning are different.
For better or worse, this case is something of a unicorn (or a Unicorn Spirit Animal, as Lupulin’s 4th anniversary fruited ale was called). Breweries have no communal system to dispose of grain, or even collective information on best practices of grain disposal. Instead, each brewery must figure out their own system through trial and error. That’s where the Brewing a Sustainable Future project comes in. We’ve been partnering with brewers and the Minnesota Craft Brewers Guild to research and implement both short- and long-term solutions to increase sustainability in the brewing process. We’re excited to keep exploring our options—and enjoying the beers (and animals) we encounter on the way.