Pod Blasting to Determine Peanut Maturity

Kelly Marshall

peanutsIn case you thought you’d seen it all, peanut farmers are using a new precision tool- the pressure washer.

For many years, growers have used a pocketknife or other sharp object to scrape away the outer shell of the peanut to determine the level of maturity. Now, reports Kris Balkcom, a peanut research associate with the Alabama Cooperative Extension System, the adoption of lightweight pressure washers gives peanut producers a better way.

The process requires different equipment that pod scraping, but using a pressure washer with a PSI of 1300-1600 makes it more efficient and quicker.  “Many of the immature pods are full of water, so it is easy to tear them apart,” Balkcom said. “Using a lightweight pressure washer will prevent the destruction of the pods.”

By keeping the pod intact producers have a more accurate maturity reading to plan harvest.  “Producers need to be able to scrape off the outer layer of the hull to see the color,” Balkcom notes. “The color of the inner hull helps to determine the level of maturity.”

Technique is important to the process as well. After pouring pods into baskets made of expansion metal with grated sides and a subfloor midway up the cylinder, growers use a turbo nozzle to blast the pods. The screen-like sides of the container and subfloor allow the water to run out of the peanuts, taking the outer hulls with it and leaving pods behind, ready to be placed on a profile board for analyizing. This video from the Extension office demonstrates the procedure.

“The distance between the wand and the pods is important,” Balkcom said. “Keeping a good distance will prevent the pressure washer from destroying the peanuts.”

“Peanuts are indeterminate, so the plants flower from 40 days of age to harvest,” he adds. “There will be a mixture of all ages of peanuts in the basket. Pod blasting will help to determine the most optimum time for harvest, the best average grade and the most weight to market.”

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