There, she engages in what she calls "a very nice trade": a bucket of the brewery's spent grain for a batch of her cookies and doughnuts.
Lynch uses the grain, remnants of the beer-making process, to make hefty, nubby-textured loaves of beer bread, one of her best-sellers. The bread is ideal for the bakery's daily toast topped with ricotta, fruit and nuts, and far more interesting than regular whole-wheat, she said.
"I use beer as well as the grain so it lends it that extra flavor, and you also get better texture," Lynch said.
Janet Fuller says if you want spent grains, brewers will gladly give them up:
Chicago's craft beer boom doesn't just mean more beer. It means a lot more spent grain, a nutritious and highly perishable byproduct the beer-drinking public doesn't think much about but which every brewery must deal with in spades — or rather, tons.
Lynch's arrangement with Revolution barely makes a dent in the vat of spent grain the brewery produces every week, but it is an example of tasty resourcefulness that brewers around town are all too happy to support — except when they can't.
All beer starts out as grains that are crushed and mixed with water to draw out the sugars. That drained liquid, called wort, goes on to become beer. And the leftover wet grain?
"It's food," said Mitchell Dushay, assistant professor of biology at Illinois Institute of Technology and craft beer enthusiast who has studied spent grain. "It's high in protein, low in carbohydrates and high in fiber."
But here's the rub: It spoils within days.
"It's fine after 24 hours, but after that, it gets this weird, funky banana smell that starts to get under your skin," said Half Acre Beer Company's Gabriel Magliaro.
The options for breweries generally come down to two: give it away or throw it away.
The common practice in the industry is to give the grain to farmers to use as animal feed. It's a win-win. Large brewers who produce a lot of it save on disposal and farmers get nutritious feed for little to nothing. Goose Island Brewery's grain, all 10 million pounds of it annually, goes to a dairy cattle farm in Indiana. Lagunitas' grain, about 420,000 pounds weekly, goes to a Wisconsin farm, with a small portion reserved to make spent-grain brownies for its taproom.
Last fall, the FDA proposed new animal feed rules as part of the Food Safety Modernization Act requiring breweries to dry and package spent grain before giving it to farmers. But the agency backed off after pushback from breweries and farmers, who argued the rules were cost-prohibitive and unnecessary. (The revised proposal is now open for public comment.)
For many of the city's smaller craft breweries, finding a good use for spent grain remains a challenge. It's a matter of logistics and space, or lack thereof.
For Jason Klein and Brad Shaffer of the one-room Spiteful Brewing in Ravenswood, "We would love to do something with it. ... The question is where do we put it?" Klein said.
They produce about 1,000 pounds of spent grain a week, "too much for a small producer, but not near enough for a farmer. For them to come get it, it's just not worth it," Klein said. He has given some to friends of friends who are trying to start a bakery, but otherwise, it gets tossed.
Half Acre for years gave much of its grain to a small farmer, "but as we've grown, we sort of outgrew his capacity," said Magliaro. "Right now, we're going to a landfill, which is terrible."
He said that will change once Half Acre's second brewery in Bowmanville is up and running by year's end, doubling the brewing capacity. The new brewery will have enough outdoor space to store spent grain from both sites and will allow another farmer, whom Magliaro has already lined up, to cart away a tractor-trailer's worth.
"We'll have a commodity at that point," Magliaro said.
For other breweries, it comes down to values. Three times a week, a truck hauls eight to 10 yards' worth of spent grain and yeast from Metropolitan Brewing's Ravenswood facility to a landfill.
"As we are a vegan brewery, we will not send our grain to the animal farming industry, but we are open to other uses," said founder and head brewer Doug Hurst. "While it may not seem that landfilling spent grain is environmentally friendly, we feel that the animal farming industry is much less environmentally friendly."
Breweries ultimately are in the business to sell beer and make money. But Revolution owner Josh Deth argues that every brewery's mission should include "being responsible about your byproduct and figuring out what to do with it."
Much of Revolution's spent grain, about 250,000 pounds a week, goes to the same farmer who takes Goose Island's grain.
Revolution's other main recipient is Growing Power. The urban agriculture nonprofit uses it for compost at its seven-acre Iron Street Farm in Bridgeport. Mixed with other nitrogen-rich food scraps, "it keeps things nice and warm," said compost manager Brian Ellis.
Growing Power also picks up about 2,000 pounds of grain a week from Piece Brewery and Pizzeria in Wicker Park and is looking to add a third brewery, Ellis said.
At Brobagel, next door to Piece, you can buy a beer bagel made with the brewery's spent grain.
But even with Piece's grain going to Growing Power, Brobagel and the occasional home gardener and chicken coop owner, Piece brewer Jonathan Cutler said the brewery still throws out at least a third of what accumulates.
Brewers will agree spent grain has plenty of untapped potential. That was the conclusion of a 2011 student research project overseen by IIT's Dushay and Philip Lewis. The study explored alternative uses for spent grain and the associated costs, which hinder the adoption of some of these viable options.
"You can use it as building material. You can make paper out of it. You can dry and grind it into food for people," Dushay said. "It's kind of one of these hidden problems that no one thinks about that's just screaming for a resolution."
One example cited in the study is close to fruition. The anaerobic digester at The Plant is about 75 percent complete and should be running next year, said Kassandra Hinrichsen, marketing and education coordinator for Plant Chicago, the nonprofit arm of the sustainable food production center.
The digester will convert spent grain (from a yet-unnamed brewery that will be moving into The Plant) and the rest of the building's food waste into biogas, which in turn will fuel a generator that will supply heat and electricity to the building.
Other plans for spent grain at The Plant include pressing it into briquettes to fuel an oven for one of its bakery tenants and using it for fish feed in the basement aquaponics farm, Hinrichsen said.
There's nothing to stop breweries from giving spent grain to curious home cooks and gardeners. Breweries may not advertise it, but many are open to it.
"If you come to the back door and knock and say, 'Hey, can we have some grain?'" Cutler said, "'we're like, 'Absolutely.' "
Even Dushay, the professor, eats the stuff. He gets the grain from breweries around town and stores it in empty yogurt containers.
"I mix it with yogurt and maybe some Grape-Nuts or raisins. My freezer is full of it. And I always bake with it. It's fantastic in bread," he said.
Recently, head brewer Jim Cibak gave her a growler full of wort to play with. Given wort's high sugar content, Lynch thought she could cook it down to concentrate the flavor before adding it to dough.
Indeed, the wort made for nice, soft beer bread. She also made wort butter. But it was a short-lived experiment. Unlike spent grain, brewers actually need wort.
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