Ben and Jerry, meet Tom and Will.

Thomas “T.J.” Paskach, graduate assistant in chemical engineering, and Will Schroeder, who earned his doctorate in chemical engineering at Iowa State, have developed an improved method for freezing ice cream using liquid nitrogen.

The traditional method is to pour liquid nitrogen and an ice cream pre-mix into a bowl and stir it really fast, Schroeder said.

“Then you scoop it out and put it in bowls for people to eat,” he said.

That method can only serve a handful of people because the process was not efficient, Paskach said. Many times they created a rock of ice cream that was 320 degrees below zero Fahrenheit.

“It is difficult to do,” Schroeder said. “It is dangerous and just is not practical.”

Paskach and Schroeder wanted to develop a safe way to make liquid nitrogen ice cream to serve a large number of people.

Using a patent-pending mixing tube, the researchers combine liquid nitrogen and an ice cream pre-mix that is “flash-frozen” in milliseconds.

“The faster you freeze ice cream, the creamier it will be,” Schroeder said.

The ice cream is then sprayed into a bucket, from which it is scooped out and eaten.

Paskach and Schroeder began making their version of liquid-nitrogen ice cream for the public at the 1999 Veishea celebration.

The prototype machine was only bench-top scale and was not perfect, Schroeder said.

“The ice cream did not come out consistent,” he said, “but we served free ice cream to 1,500 people.”

In 1999, Paskach and Schroeder formed a business called Nitro Cream Partnership. At the same time, they applied for a patent for their machine. They approached the ISU Research Foundation, which manages intellectual property for Iowa State.

Schroeder said the foundation then had a lawyer set up the patent.

“The process takes years,” Paskach said.

“We are still waiting,” Schroeder added.

While they wait, they continue to tinker with the machine.

“We wanted to redesign the mixing tube for cleanliness’ sake,” Schroeder said.

This small adjustment made a big change in the final product.

“Suddenly, the ice cream came out perfect,” Paskach said. “I was like, `Oh my God!’.”

But the machine itself was still not quite right.

The first system was controlled by sound, Schroeder said.

“We listened to the sound in the mixing tube and turned a valve by hand to re-adjust. It was like listening to a large cappuccino machine.”

After the Veishea experiences, Paskach and Schroeder started to do some market research. They wanted to share their ice cream at the Iowa State Fair.

“We called Campbell’s Concessions, who run a lot of the ice-cream booths at the state fair,” Schroeder said.

“We heard about all the numbers about what you could make at the fair.”

But in order to feed the throngs of hungry fairgoers, Paskach and Schroeder wanted to improve their machine even more.

“We had to scale it up much further,” Paskach said. “We also needed to make it sanitary and computer controlled. We did not want to control it by sound anymore.”

A dispensing unit was added to the machine. That improvement almost became Nitro Cream Partnership’s undoing.

“Two days before the state fair, the dispenser was a $5,000 boat anchor,” Paskach said.

There was a bigger problem.

“It just would not dispense any ice cream,” Schroeder said. “So we got a plastic box and filled it just like [we] had at Veishea,” he said.

They weren’t there yet. On the first day of the State Fair, the mixing tube of Nitro Cream Partnership’s machine broke.

“The tube cracked and we stayed up all night fixing it,” Paskach said.

“We wanted to quit,” Schroeder said.

But they came through.

“We fixed it, and the rest of the fair was an incredible success,” he said.

And as it turned out, losing the dispensing unit proved to be a step for success for Nitro Cream Partnership.

“The novelty of the whole thing was the sound and the visual appeal,” Paskach said. “The dispenser killed the sound. Had it worked, we may have failed.”

Nitro Cream Partnership grossed more than $30,000 at the State Fair.

“It was barely enough to pay off everyone and the materials, so there was no real profit,” Schroeder said. “But we still own the machine as an asset.”

Paskach and Schroeder also have attended the Clay County Fair and the Tulsa State Fair in Oklahoma, and they were invited to the Minnesota State Fair.

“Getting into these fairs is not an easy task,” Schroeder said. “But our new technology helped us get into them.”

Paskach and Schroeder have renamed their business Nitro Ice Cream and are thinking about opening a store in Ankeny.

“We thought about Minneapolis and Chicago, but Ankeny is just better for logistics,” Paskach said.

“We are trying to open by April . Our ultimate goal is to open several company stores in the Midwest,” he said.

But for now, the two are content with enjoying the sweet product of their innovation, Schroeder said.

“But [branching out] is a very complicated process and is much further down the road,” he said.