NIR (or near-infrared) technology works by shining a light on the potato as it travels through the sorter. Part of the light will be either absorbed or reflected by the potato. By measuring the ratio of absorption to reflection, growers can tell if there is soluble sugar in the potato, a sign of zebra chip.
CSS Farms, which provides potatoes to potato chip giant FritoLay, has been using the technology to spot zebra chip at its Texas base for a year. Taste Technologies general manager Bob Shaw said he was getting good feedback about the product.
Taste Technologies and sister company Compac Sorting Equipment, of which Bob Shaw is also general manager, had sold about 200 sorters with NIR technology, mostly to US growers. Most were used for spotting defects in fruit. About 18 sorters had been sold to test for zebra chip.
Image courtesy ARS
