New University of Idaho Research Sheds Light on Best Way to Illuminate Idaho Potatoes

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EAGLE, ID, January 12, 2006 - Accent lighting is becoming increasingly popular in the supermarket. Carefully aimed bulbs can enhance avocadoes' green waxy shine, boost bananas' sunny colors and make radishes, grapes and blueberries look positively mouth watering.

According to new research conducted by scientists at the University of Idaho Extension, however, some lights work better on potatoes than others. The study showed that certain bright overhead lights speed the rate at which potatoes turn green and that's a consumer turn-off.

Fortunately, the scientists were able to identify what type of lights flatter the natural beauty of the russet, without compromising the integrity of the spud. According to the world's foremost experts on Idaho Potatoes, the Idaho Potato Commission (IPC), there are also several other manageable recommendations that will ensure that America's favorite potatoes maintain their trademark consistent quality, in addition to the lighting solutions.
IPC and University of Idaho Extension Partnership

According to Seth Pemsler, VP - Retail/IPC, research by Dr. Olsen, Extension Potato Specialist at the University of Idaho, and other scientists associated with the University is extremely useful because it helps the IPC understand every aspect of the potato. In this case, the lighting research helps the Idaho Potato industry educate retailers on how to maximize the quality of potatoes in their produce departments.

"We continually work with our retail partners to help them design optimum display conditions for Idaho Potatoes, "said Pemsler. "We pride ourselves on being the leading experts on potatoes and this type of research is invaluable to us. We applaud the efforts of the scientists and we appreciate the ability to practice what we learned. The ultimate benefit is that the consumer is going to be assured the consistent quality that is our hallmark."
Understanding The Greening Effect

If you think back to your high school biology classes, certain plants contain chlorophyll. Potatoes are the living reproductive tissue of potato plants and they accumulate chlorophyll on their surfaces when exposed to either natural or artificial light. The bright lights actually speed up the rate at which potatoes turn green.

The Idaho Extension potato specialist who conducted the study acknowledges that accent lighting works. "It's effective. It makes food glow and pulls you over and says 'Look at me!'" But Dr. Nora Olsen also recognizes that what might work for all of the other fruits and vegetables in the store does not promote good results in potatoes.
Study Methodology

To determine which light sources have the least impact on potatoes, Olsen and Support Scientist Tina Brandt evaluated six of them: fluorescent (two types), halogen, ceramic metal halide, fiber optic, and fluorescent with filter.

The scientists measured the different light sources' effects on potatoes inside specially constructed, 4 ft. x 4 ft. x 7.5 ft. "light rooms."

During nine days in light intensity comparable to retail levels, potatoes under fiber optic lighting turned green at the slowest rate. Spotlighted in the produce aisle, their shelf life would be a half-day to a full day or even longer, Olsen estimates.
Recommendations to Prevent Greening

The study showed that fiber optic lighting -- or a combination of fiber optic accent lighting and standard fluorescent lighting -- will help retard greening in the retail store yet highlight the commodity for consumer eye-appeal.

As the marketing agent for the world's best selling potato, the IPC's job is to ensure that its potatoes are displayed in conditions that not only complement the russets, but protect and nurture the taste and performance enjoyed by the end-user, the consumer.

"We recognize the conundrum that this research presents our retail partners, but there are several short-term and easy to execute recommendations that will significantly lower the potential for greening," said Pemsler.

For instance, the IPC's Retail Promotion Directors encourage produce managers to rotate the potatoes in the displays at night (switch the potatoes on the top with the potatoes on the bottom) and/or to cover the potatoes at night with a light-blocking material.

Although Idaho is famous worldwide for its premium potatoes, some consumers don't realize that only potatoes grown in the Gem State can wear the "Grown In Idaho" seal. Both Idaho® Potatoes and the "Grown in Idaho®" seal are federally registered Certification Marks that belong to the IPC. These Marks ensure that consumers are purchasing potatoes that have been grown in the state of Idaho.