When Will Schroeder graduated from Iowa State in 2001 with a Ph.D. in chemical engineering, he could have landed a research job — in fact, he had an offer on the table.

“My research was in petroleum catalysis. I would be working for Exxon Mobil,” Schroeder said.

Instead, he followed through on a flash of inspiration from two years earlier, stuck around Ames and went full-time into the ice cream business with Blue Sky Creamery.

In 1999, Schroeder and his partner, Thomas “T.J.” Paskach, were searching for a way to improve the chemical engineering department’s Veishea display.

The booth typically gave out ice cream made with liquid nitrogen, but the traditional method — pouring the liquid nitrogen into a bowl of pre-mixed ingredients — didn’t always produce the best results.

“You have a hard chunk over here, a liquidy chunk over here,” Schroeder said. “You can never serve more than a few people with that method.”

So Schroeder and Paskach began experimenting. The result was a device called a mix tube, which changed the dynamics of the freezing process.

“What we invented is a way to do it continuously,” Schroeder said. “It continuously shoots out hard, consistent ice cream.”

The original prototype was rough, Schroeder said, but the idea sparked a lot of interest.

“We thought this could be something more than just a Veishea display,” Schroeder said.

After their initial success, they moved to get a patent. Iowa State had the first shot at the intellectual property discovered, because ISU facilities were involved in the idea.

“We used our own money, but we did it in a lab with lab facilities,” Schroeder said.

But the two didn’t really mind giving up patent rights, he said.

“We didn’t really want to start a business; we just thought it would be cool to get a patent and not pay for it,” Schroeder said with a laugh.

But as they explored the concept and worked with the prototype, the possibilities became clear, and they ended up in business anyway, starting off at the 2000 Iowa State Fair.

Their first year at the fair led to more demonstrations, as well as other expansions.

“After two years at the fair, people kept saying, ‘where can I get this after the fair?’” he said.

Encouraged by their success, Blue Sky moved into franchising, with ice cream cafés opening in Des Moines and St. Louis.

However, Schroeder said that the recent economic downturn has slowed the growth of the business and changed the game.

“In a down economy, people don’t have the money to open up an ice cream shop,” Schroeder said.

Instead, the focus of the business is now on franchising what gave Blue Sky its start: mobile concessions serving up scoops at events like state fairs, craft shows and corporate dinners.

Although mobile vendors are on their own for events, they need training, supplies and support. Schroeder is now president — Paskach departed earlier this year but still consults on technology issues.

Although risky, trading oil for ice cream has been a good move, Schroeder said.

“This is the time to give it a shot, when you’re young,” he said.