High-capacity sorter works for spinach, leafy greensA new integrated sorting system from Key Technology can increase belt speeds for fresh spinach and other leafy greens by 30% while removing foreign material and wilted product with a false reject rate of less than 1%.

“Fresh spinach can be very hard to sort because the leaves are light and flat, so they fly like a sail. It tends to lift and roll, which makes it difficult to stabilize for accurate inspection and the targeting of rejects. Overcoming this challenge required a series of very specialized product handling solutions,” Marco Azzaretti, Key Technology’s advanced inspection systems product manager said in a news release.

The system includes an Iso-Flo fines removal shaker, an acceleration belt and a Manta 2000 series digital sorter. The Manta device has three top-mounted visible infrared cameras, two bottom-mounted visible infrared cameras and two fluorescence-sensing lasers, according to the release.

Grower-shipper Muzzi Family Farms LLC, Watsonville, Calif., is using the system to sort fresh spinach at its subsidiary, Blue Ribbon Frozen Foods, according to a spokeswoman for Key Technology, which is based in Walla Walla, Wash.

The Key Technology system can be used for fresh spinach, other leafy greens and fresh-cut greens such as cabbage, according to the release. When sorting spinach, the system can handle up to 13,000 pounds an hour. With cut romaine or iceberg lettuces, the system handles up to 12,000 pounds an hour. Cut cabbage has the best rate with the sorting system, reaching speeds of 50,000 pounds per hour, according to the release.

The system can be added at the receiving end of a packing line or after the cutting process.

A three-deck Iso-Flo fines removal shaker is the first step, removing small objects such as dirt clods and sticks. The second step, an acceleration belt, spreads, “singulates” and stabilizes product before it goes through the sorter.

High-definition cameras in the Manta 2000 series sorter can recognize color, size and shape to detect leaf defects including mechanical damage such as bruising, decay and color defects such as yellow caused by sunburn. When sorting chopped cabbage, romaine or iceberg lettuce, the laser is also configured to detect and reject core, according to the news release.