Chestnuts roasting on a ... CT scanner?
One bad chestnut may not spoil the whole bunch, but it can do a lot of damage to an industry’s reputation, to say nothing of its business.
In an effort to make sure chestnuts make it to market in good condition, a team of Michigan State University researchers is working to develop a noninvasive method of detecting internal decay in the fruit (despite the name, chestnuts are technically a fruit).
What the researchers are doing is assessing the various imaging techniques currently available.
“We can’t destroy the product, so we are testing some of the same technologies that the medical world uses,” said Daniel Guyer, professor of biosystems and agricultural engineering who is leading the research team.
So far it appears that CT scans, as opposed to X-rays or MRIs or other techniques, work the best.
“X-rays look all the way through something, so you get a composite blurring effect,” Guyer said. “An MRI is more expensive and is much slower in providing images. CT scans provide a more detailed, 3-D image quicker.”
A CT – computerized tomography – combines a series of X-rays taken from different angles and computer processing to create cross-sectional images.
Guyer and his team are working with researchers across several disciplines to determine a method that can be used for not only chestnuts, but a host of other food items.
“The goal is to develop a system that will automatically sort the internal quality of things that we can’t use current technology for,” said Irwin Donis Gonzalez, a doctoral student working on the project. “We have to take what the human mind does in interpreting images and translate it into an algorithm to develop a reliable computer-based model.”
Although in its infancy, the chestnut-growing business is starting to catch on. The United States produces only about one percent of the world’s chestnuts. But in the United States, the state of Michigan leads the nation in chestnut production.
“Agricultural diversity is very important,” Gonzalez said. “Think of last spring when we had some early heat, then a frost. Michigan’s apple and cherry industries got hit hard, but we did have chestnuts.”
In a perfect world, chestnuts and other foods are imaged at harvest time. Chestnuts, in particular, are important to get to early in the process, as they are perishable, similar to apples.
“If I sell you a pound of nuts and it’s got one or two really bad ones in it, you’re not going to be a return customer,” Guyer said. “That’s what we’re trying to avoid.”