Researchers at Washington State University have started a project to develop thermal sensors to prevent apple sunburn. WSU Associate professor, Lav Khot said this research will focus not only on the burn, but the heat stress that can lead to disorders while the apple is in storage.


"We're installing the sensors in the canopies'. We're taking a RGB camera attachment to gauge a few fruits in the canopy and the canopy temperature as well.”

The system he noted will activate a cooling mechanism when the fruit’s surface temperature nears the point of sunburn. Khot noted during a typical year, Northwest apples are subject to heat stress at least ten plus days during the growing season, which he says results in 20% to up to 50% of the fruit sustaining a sunburn.

"Using a thermal gun to get the fruits' temperature, we are estimating the fruit's temperature in real time every few minutes. It's telling you how your fruit in that block is doing in terms of the heat stress."

Several organizations are assisting the sunburn research financially, including the Washington state Tree Fruit Research Commission, USDA and National Science Foundation. Currently, the project is being tested in an orchard of Cosmic Crisps and Honeycrisps in the Yakima Valley.

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