STEM To Steam: How Coffee Is Perking Up Engineering Education | KUOW News and Information

STEM To Steam: How Coffee Is Perking Up Engineering Education

Sep 8, 2016
Originally published on September 9, 2016 2:57 pm




Think about all those chemical reactions when you roast the beans. "The roaster we use, a chemical engineer would call that a fluidized bed reactor," Ristenpart says. When hot water extracts tiny particles of flavor and oil from the ground-up beans, "we would call that mass transfer." And what drives hot water through an automatic drip-coffee machine? Fluid dynamics, of course.

Together, Ristenpart and Kuhl turned the coffee problem into a seminar for first-year engineering students. The first year, in 2012, they had 18 students. The next term, 300 students signed up. Last year, the course, called Design of Coffee, was the most popular elective class at the entire university. It fills the largest lecture hall on campus. Last year, the course was offered each term, and more than 1,500 students took it — roughly a quarter of the freshman class. Most of them weren't even engineering students.

"We have an army of teaching assistants," Ristenpart says. "Every graduate student wants to work with this class."

In the coffee lab, teams of students start with identical unroasted coffee beans and compete to produce the best-tasting product. Ristenpart says they end up with "wildly different" version of coffee. Last term's winner blew away the competition with an "aeropress" method, similar to a French press, that produced coffee with a smell that reminded people of blueberries.

Molly Spencer, a graduate student in the Food Science department, has been a teaching assistant for the course. She says it's perfect for college students.

"That's when people start drinking coffee, a lot of times, so it's very relevant for their personal lives, too," she says. According to Spencer, the class turns some of these "overcaffeinated undergrads" into more discerning coffee consumers. They learn, for instance, to appreciate coffee just as it is, without any milk or sugar added.


Ristenpart says there's a gaping void of academic research on coffee-making. Scientists might study what happens in the green coffee beans when they are fermented, immediately after harvest, or ways to "maximize the transfer of flavor molecules that you want" into your cup during the brewing process, while leaving those bitter-tasting molecules behind.

Ristenpart is now director of the UC Davis Coffee Center, which is starting to take over a newly vacant, 6,000-square-foot building on the UC Davis campus. It's not far from the Robert Mondavi Institute for Wine and Food Science, a world leader in research on grapes and wine, which Ristenpart sees as a model for his work. "There's nothing like it for coffee," he says.

At this point, though, the Coffee Center is little more than a building that's filled only with Ristenpart's dreams, while the Mondavi Institute is a bustling enterprise with dozens of full-time faculty and staff. Part of Ristenpart's job will be raising money to turn his dreams for the Coffee Center into reality.

The first grant was announced this week. Peet's Coffee is donating $250,000 to help renovate the building and build a pilot coffee roastery.

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Coffee and college go together quite well, as many students and former students can testify. Now one university is using coffee to teach chemical engineering, and it's been wildly successful. NPR's Dan Charles explains.

DAN CHARLES, BYLINE: It's not easy studying chemical engineering. Bill Ristenpart, who teaches at the University of California, Davis, says there's a lot of basic math and physics at first. Students don't get to do anything practical with that knowledge.

WILLIAM RISTENPART: And if you don't really have a good sense of what the, you know, goal is, then it becomes very challenging to stick through a pretty tough curriculum.

CHARLES: So colleges are trying to give students a better sense of what that goal might be with a hands-on project early on. A few years ago, Ristenpart and a colleague were looking for such a project. And it struck them - coffee making. It's all chemical engineering. Think about it, all those chemical reactions when you roast the beans.

RISTENPART: The roasters we use, a chemical engineer would call them a fluidized bed reactor.

CHARLES: And when hot water extracts coffee flavor and oils from the ground up beans?

RISTENPART: We would call that mass transfer.

CHARLES: What drives water through an automatic drip coffee machine? Fluid dynamics. So they created a course - design of coffee. Teams of students competed to create the best-tasting coffee while using the least amount of energy. They got 18 students the first year, the next year - 300. Last year, it was the most popular elective course on the entire campus. A quarter of the freshman class took it.

Molly Spencer, who is a graduate student in food science, has been a teaching assistant for the course. For college students, she says, it's perfect.

MOLLY SPENCER: That's when people start drinking coffee a lot of times - in college. So it's very relevant to their personal lives, too.

CHARLES: Is there a lot of coffee drinking going on in these labs?

SPENCER: Yeah, over-caffeinated undergrads.

CHARLES: (Laughter).

And Bill Ristenpart's coffee fixation has taken a new turn. Instead of using coffee to teach engineering, now he wants to use engineering to learn more about coffee. He's raising money for a whole new coffee research center at UC Davis. He says there's a lot we can still learn about coffee. Dan Charles, NPR News. Transcript provided by NPR, Copyright NPR.