U prof uses MRI for food research

Minnesota is one of three universities in the nation to use MRI for food science and horticulture research.

Beth Hornby

Like doctors who can examine a beating heart without making a single incision, biosystems and agricultural engineering professor Roger Ruan can virtually dissect a bean, layer by layer, while it is safely sealed in a small gray box on his desk.

The box, known as a magnetic resonance imaging device, is what Ruan said makes most of his research on food properties possible.

The machine is so vital to his research that the University spent $135,000 to purchase an MRI device exclusively for the biosystems and agricultural engineering department in June.

The University is one of three universities in the nation to use MRI for food science and horticulture research.

Ruan uses the machine to research increasing shelf life, maintaining food’s nutritional value when it is cooked and measuring bacteria levels to determine when food becomes unsafe to eat.

“During cooking or fermentation, for example, we can know exactly how chemical and nutritional compositions change,” Ruan said.

Ruan said looking at the movement of water in a food product and graphing changes in temperature and chemical composition during food preparation are essential services he can do with the MRI that will not disturb or skew results.

But the University is not the only one with a watchful eye on Ruan’s research. General Mills, Pillsbury and the U.S. Department of Defense all have a stake in his experiments.

“The U.S. Department of Defense supports my research projects because they are interested in food storage and transport,” Ruan said.

Additionally, General Mills contributed $165,000 to the MRI purchase – more than half the machine’s $300,000 total cost.

General Mills spokeswoman Kirstie Foster said the company is interested in Ruan’s research because it wants to understand water in food products.

“As we vary product forms and manufacturing process, it lets us understand the state of water in the food system,” Foster said. “It can be a great benefit as we design new products and processes.”

Ruan said his research has become more feasible since MRI was developed in the 1970s.

Five years ago, he said, a new MRI device cost more than $1 million.

“MRIs were difficult to access because they were so expensive,” Ruan said. “In the next 10 years we will see a lot of faculties start to use this technology now that the price has dropped.”

Despite increasing affordability, Ruan said, his work remains unique because few people are trained to use MRI machines properly.

“It takes a lot of training before you can fully utilize this technology,” he said.

Lide Chen, a visiting research scholar from Beijing, uses the MRI device to analyze the water content of dry beans. He said it took him a lot of time to understand the MRI because before coming to the United States he had never used one.

“A lot of experts in this area find certain machines such as this not so easy,” Chen said.

Ruan said the scientific community increasingly appreciates MRI applications. This year, MRI inventor Paul Lauterbur received a Nobel Prize for inventing the MRI device, which he did in 1972.

Ruan said he is now awaiting a newer and larger magnet he ordered from England so he can research larger samples.