STOCKTON, Calif. — Following the success of a new 20-lane optical cherry grader-sizer in its Wenatchee, Wash., facility last season, Stemilt Growers LLC is installing a 40-lane machine in its Stockton, Calif., packinghouse in time for the start of this season.
The Wenatchee-based grower-shipper also plans to double optical grading-sizing capabilities in Washington this season with the addition of a second 20-lane machine, said Briana Shales, communications manager.
“We really see it as the wave of the future in cherry packing,” she said, adding it will allow Stemilt Growers to produce a more consistent pack for its customers with significant labor savings.
“It does take the human error out of it, which is why you see a better pack-out,” Shales said. “There will still be human sorting going on because nothing is perfect.”
The project at the Chinchiolo Stemilt California LLC facility involves completely retrofitting the A packing line and installing a 40-lane computerized optical grader-sizer from Lugo, Italy-based Unitec S.p.A., said Erick Stonebarger, Stemilt sales/special projects representative based in Stockton.
Stemilt began construction in July 2013, not long after the completion of the California cherry season.
This winter, operators traveled to Chile during the southern cherry season to learn about the system and software upgrades Unitec had made, he said.
Once the California cherry season finishes in June, those operators will head north to Wenatchee for the cherry and apple season there.
Stonebarger said the company hopes to have the Stockton system operational by early April. This will allow about 10 days for testing and debugging before the first loads of fruit come in from the south San Joaquin Valley.
“We have a decent idea what to expect, but with any new line, there are always going to be nuances you have to figure out,” he said.
The packing operation involves small flumes of chilled water that gently convey cherries from dump tanks to the final packing stations, helping to reduce mechanical damage. Stonebarger said Stemilt opted to use chilled water throughout to maintain the cold chain.
Along the way, the fruit are separated and moved onto rollers that carry them under two sets of cameras that use Unitec’s proprietary Cherry_Vision.
The first set shoots pictures from four different angles for color, quality and defects. The second set images the top of the fruit for sizing. Computers process the information and kick the fruit out in the appropriate packing lane.
In the past, all of the hand grading was done at the front of the line, so everyone received the same quality, Stonebarger said.
The new system will allow Stemilt to dial in different quality parameters and packs for individual customers.
“In general, you have tremendously more consistency and the ability to manage the consistency in the box, particularly with differentiating colors and firmness,” he said.
The goal is to provide a consistent eating experience for consumers and more repeat customers for retailers, Stonebarger said.
Beginning this season, 80% to 90% of Stemilt’s California cherry crop will be run through the new grader-sizer, Shales said.
Although the new machinery will significantly reduce the number of human sorters, it will increase the number of workers needed on the back end because of the speed with which it grades and sorts, Stonebarger said.
“So we save a chunk on people on the sorting but we’ve had to double the personnel on the back end on the filling,” he said.