Chelsey Lowder, front, and Rhett Spear slice chips at University of Idaho’s Research and Extension Center kitchen in Aberdeen, Idaho.

ABERDEEN, Idaho — At the University of Idaho’s Research and Extension Center kitchen in Aberdeen, Idaho, scientific aide Chelsey Lowder sliced a potato into thin, translucent ovals and let them dry before dipping them into a fryer.

Once the hot oil stopped bubbling, she removed the basket and placed the finished chips in a row adjacent to a color chart. They were a tad dark but within the industry’s acceptable color range, said Rhett Spear, UI Extension potato variety development specialist.

They were working ahead of National Potato Chip Day, March 14.

University of Idaho and the U.S. Department of Agriculture’s Agricultural Research Service work together on a potato breeding program based in Aberdeen. The team spends most of its time developing russet potatoes for making french fries. But the pipeline includes a steady stream of spuds for chipping.

“Chips in general are made from potatoes with a high specific gravity, which gives a better chip texture,” Spear, who oversees evaluating potatoes in the Aberdeen program, said in a UI release. Producers of chips “want a round potato, and usually it’s a white-fleshed potato. We’re looking for a high tuber set, and tuber size somewhere between a racquetball and a baseball.”

Specific gravity is a measure of solids or starch content relative to the amount of water, according to the Idaho Potato Commission. Low moisture means high solids content.

In Aberdeen, the variety development process starts with Rich Novy, USDA Ag Research Service potato breeder, making a cross in a greenhouse. Some 10-15% of his breeding crosses are chippers. Researchers and representatives from industry, such as American Falls-based R&G Potato Co. and Michigan-based Walther Farms, help select specimens to keep.

In the Northwest, the Aberdeen team and potato breeding programs at Washington State University and Oregon State University work together in the Tri-State Potato Breeding Program — which released Gem Chip in 1989, the Aberdeen-produced Ivory Crisp in 2002 and Willamette in 2003.

After several generations in Aberdeen, the best crosses move on to the Tri-State Trials and are grown in all three states. The best of those varieties graduate to the Western Regional Trials that include Colorado, California and Texas.

The National Chip Processing Trials, which Potatoes USA leads, include hundreds of entries. Each participating program — the University of Florida is slated to be added, joining the Aberdeen team and 11 others — evaluates them on about 20 variables such as yield, storage attributes and fry color.

After candidates are in the system for five or six years, a handful that look especially good go into the Potatoes USA Snacking, Nutrition and Convenience Trials, said John Lundeen, Potatoes USA research director.

The first year in the national chip program, “you’re looking at 17 hills. That’s like one row of potatoes,” he said. “By the time you get to the SNAC Trials, we are committing a third of an acre. That’s what they need to run through a chip plant to see how they process.”

The trials wrap up before an annual meeting hosted in early December in Chicago, where researchers and industry discuss results. “You go from tens of thousands down to just a handful in final testing, and not even all in that handful get commercially released,” Lundeen said.

Novy made the initial cross of another Aberdeen breeding line that’s showing great promise, UI said. A Michigan State University facility is developing pathogen-free tissue culture plantlets for production of certified seed for more intensive evaluation by the national program.