M-TEC engineers developing automated chile destemmer

New Mexico State University engineers are resolving one of the last issues of mechanized chile harvesting – destemming the chile pod.

During traditional hand-harvesting, as the pod is removed from the plant a twist of the wrist leaves the stem’s uneatable pedicle and calyx on the plant. As the traditional labor force decreases, chile farmers are turning to mechanized harvesting, however the important step of removing the stem is not accomplished by the machinery in the field.

“Automatic harvesting and destemming are critical improvements for the chile industry. If New Mexico wants to keep its chile industry and retain our status of chile capital of the world, our industry must automate. Chile is the heart and soul of New Mexico and NMSU is key to ensuring that we keep our chile,” said Gene Baca, vice president of Bueno Foods in Albuquerque.

Through the NMSU College of Engineering’s Manufacturing, Technology and Engineering Center (M-TEC) engineers are working with the New Mexico Chile Association, through funding from the New Mexico State Legislature, to develop a machine that will remove the stem. After three prototypes, Ryan Herbon, primary engineer on the project, says they have a process that is 80 percent accurate with green chile and 95 percent with red cayenne peppers.

The NMSU engineers have developed a system that pulls the stems off the pods. The process begins with the chiles being spread and aligned on a shaking table and troughs that move the pods perpendicular into the destemming rollers. There, the chile is compressed between rollers that incrementally increase in speed, which causes the rollers to pull the stem off the pod.

The mechanized system will be installed at the processing plants to eliminate the need for additional labor during the harvest season.