Technology Improves Peanut Grading, Moisture Detection

Helping the peanut industry grade peanuts faster and more accurately could be possible using technology developed by Agricultural Research Service (ARS) scientists at the National Peanut Research Laboratory (NPRL) in Dawson, Ga.

Engineer Hank Sheppard and research leader Marshall Lamb found that using X-ray technology to grade peanuts delivered a 98- to 99-percent accuracy rate, and was faster than official peanut-grading methods—7 minutes versus 20 minutes per sample.

The peanut industry is in a period of rapid economic and technical change, and this technology will help the industry maintain a competitive edge, according to Lamb.

Official peanut grading is labor-intensive, requiring three to six people to hand-shell, pick, sort and grade each nut. The peanut industry sought help from ARS to improve current procedures or develop new technologies that would make peanut grading more efficient while ensuring, or even improving, accuracy and quality.

Another processing problem addressed by ARS research is peanut moisture. Nuts must have a moisture content of 10 percent or less to be suitable for further processing and shelling. The ability to determine moisture before grading begins would allow processors to divert high-moisture nuts for further drying instead of discarding them. Currently, the nuts are shelled, and then the moisture content is determined.

Another engineer in the NPRL, Chari Kandala, developed an automated in-shell moisture-detection system using radio frequency that could work in tandem with the X-ray grading unit to provide peanut processors a more efficient operation.

Read more about this research in the February 2009 issue of Agricultural Research magazine.

ARS is the principal intramural scientific research agency of the U.S. Department of Agriculture.