An evaluation of ship-board scallop grading equipment.

Abstract

The efficiency of two types of scallop graders has been evaluated. One type, based on a rotating perforated metal drum, remained efficient under all test conditions whereas efficiency of the second type, a perforated metal chute, varied greatly with its length and angle of fall. Mean size of scallops selected by each type of grader has been estimated and variation in mean selection size induced by different perforation sizes has been measured. The rotary grader induced more chipping of scallop shells than did the chute, but scallops graded by a rotary grader did not suffer significantly greater mortality than a hand sorted control.