Development and Performance Evaluation of Strawberry Class Sorting Apparatus for Improvement of Packaging Center Efficiency

Strawberries are a labor-intensive agricultural product. Packaging strawberries, in particular, is time-consuming, and is a major burden on producers. In recent years, packaging centers in charge of packing operations for producers have emerged in major strawberry-producing regions; however, they are not fully capable of meeting producers’ demands. We developed a prototype strawberry fruit-class sorting apparatus that can measure the amount and value of strawberry to fix the payment from each strawberry producer at the time of shipment acceptance, through the weighing of boxed strawberries, image capture, and image processing. This prototype yielded an accuracy equal to or higher than that achieved by the manual classification of strawberries by humans; moreover, the introduction of this prototype was determined to shorten the time required by packaging workers by about 14 min per strawberry producer. These results can thus improve the operating efficiency of packaging centers. However, image processing of strawberries was found to be influenced by the background color, suggesting the need to consider the color of the cushioning material that is used to box strawberries.