COMPARISON OF VISUAL AND AUTOMATED COLORIMETERS - AN INTERNATIONAL COLLABORATIVE STUDY

Color as a fundamental quality of edible oils has been determined prim arily by visual comparison methods for many decades. The automatic col orimeters introduced recently made it possible to replace the manually operated Visual color instrument, which requires experience to master and is often subject to operator variabilities. A previous study with an automatic colorimeter, Colourscan, to measure the colors of refine d and refined bleached cottonseed oils showed good agreement (r(2) = 0 .99) with visual color measurements by means of the Lovibond-AOCS Colo r Scale. The current work is to establish a broad-scale correlation be tween the automated colorimeter and visual color measurements. In this international effort, factory-processed refined and refined, bleached , deodorized (RED) canola, corn, cottonseed, peanut, sunflower and soy bean oils, as well as refined palm olein, RED palm oil, and washed, dr ied, filtered and deodorized tallow were used. A total of 14 laborator ies from the United States and Canada, and 16 laboratories from 12 cou ntries outside of North America, participated in this collaborative st udy. The results of this study, with statistical analyses, are reporte d.