It's the Cadillac of roasters -- or maybe the Mercedes-Benz, considering its origin. The German coffee roaster Probat isn't a household name, but it's synonymous in coffee circles with high quality coffee roasting. Some of the best artisan roasters in St. Louis -- Shaw's Coffee Ltd.
, Northwest Coffee Roasting Company
and, most recently, Kaldi's Coffee Roasting Company
(more on that later) -- have been using Probat machines for years.
When I visited Northwest earlier this summer, owner Rick Milton showed me how the company roasts its beans on a vintage 1957 22-kilo Probat.
"Low-end roasters don't have the same air flow," Milton told me, comparing his Probat to newer, lesser models. "Besides that, the cast iron in the older ones really improves the roast."
The most coveted Probats (the most coveted of any brand of roaster, really) are the oldest. Yes, a certain mystique -- a sense of history and a classic design -- accompanies a vintage roaster. But the true advantage of an old-school roaster comes down to one thing: cast iron -- lots of it. Just like old cars, vintage Probats were made with more metal. (Looks like I'm really getting some mileage out of that classic car analogy.) The cast iron lends a more even heat distribution across the barrel. improving quality and consistency in the roast. As the cost of cast iron rises, however, less of the conductive metal goes into newer roasters.
Photo courtesy Tyler Zimmer
Kaldi's new Probat, packed up and ready to go.
The search for these coveted classics keeps roasters' ears to the ground for when the next one appears. A blip on the Probat-radar sent Kaldi's Tyler Zimmer all the way to Buffalo, New York, to check out a lead. When a small roaster went out of business, Tyler heard through the grapevine that there might be a unique roaster available. What he found was, literally, one of a kind. The vintage 1937 Probat G75 is the only known model to be in operation in the U.S. Probat stopped production of this model after World War II, but its history doesn't end there: The G75 was the same model used by Peet's and Starbucks in the 1970s.
When I visited Kaldi's roaster to see the new Probat, I couldn't help but think it looked like a giant Rube Goldberg machine, somewhere between a locomotive and an industrial loom. Exposed fan belts whirled on the side as the barrel and cooling tray spun. Two sets of conveyors flanked the cherry-red roaster: one sorted the beans from rocks and other detritus; another loaded beans into the roaster above my head. Three sets of burners kept an even blue glow underneath the barrel. There is a distinct charm to the beast. It has a utilitarian style (in a nineteenth century sort of way) and, despite its awkward first impression, it exuded a certain confidence in its own potential.
The community that services these antiques is very small. Kaldi's owner Josh Ferguson estimates that there might be only six people in the U.S.A. that work on refurbishing and restoring Probats and other vintage roasters. Kaldi's relied on one of the best known in the country, Marty Curtis, to rehab its new machine. Coffee roasters, like your grandma's cast-iron skillet, only get better with time. But just like that skillet, it needs to be seasoned to get the best flavor. Ferguson told me that he almost lit a whole bag of coffee beans on fire trying to season Kaldi's Probat. When it was all said and done, it took approximately a year to refurbish the roaster.
Kaldis's roaster Jeff Shafer had worked on Probat roasters previously. The Probat has a "more gentle way to develop the sugars and caramelization in the coffee," he says. "It lets you sweet talk the coffee."
A close-up of Kaldi's new Probat
As I cupped a few of the early trials that came off the new Probat, I mistook some coffees I thought I knew well. Guatemalan Santa Isabel usually has more chocolate notes on my palate, but I was surprised at how bright and fruity the flavor was -- I actually confused it for Burundi Kinyovu Lot 5.
"It's a really steep learning curve," roaster Joe Marrocco says. "With this new Probat we're going to be able to bring out flavors that weren't there before."
While Northwest and Shaw's have been roasting on Probats for years, Kaldi's had always used San Franciscans. Acquiring a vintage Probat, though, was always on the local roaster's mind. While Kadli's still has one San Franciscan in operation for smaller batches, the other sits disassembled in the corner of the warehouse, waiting for a new home.
"The San Franciscan is a great starter roaster," Ferguson told me, "but we were ready to move on to the next level."Zach Dyer is a writer living in Saint Louis. He did his thesis research on coffee farmers in Southern Mexico. Since then, he has visited coffee plantations in Costa Rica and Mexico as well as roasters and cafés across the U.S. He blogs about coffee for Gut Check every Wednesday.