Submitted to: American Peanut Research and Education Society Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 7/19/2002
Publication Date: 8/13/2002
Citation: Boldor, D., Sanders, T.H., Sheppard, H.T., Blankenship, P.D., Hendrix, K. 2002. Peanut pod lightness measured using computerized image processing system. American Peanut Research and Education Society Proceedings. Interpretive Summary:
Technical Abstract: A significant share of the peanut market is represented by bulk, in-shell peanuts. These peanuts are graded based on pod discoloration, since peanuts with an ideal buff color are preferred by consumers. This study was performed to evaluate the pod discoloration of in-shell virginia-type peanuts using a computer-assisted image processing system. Pod images were acquired using an image acquisition system and images were analyzed using image-processing software. Samples of virginia-type pods graded by USDA inspectors in New Mexico were used in this study. Preliminary research indicated that discoloration was not evenly distributed on a single pod. However, the distribution of discoloration for all pods in a sample was the same when pods were sequentially rotated to measure discoloration on four different surfaces. Pod discoloration was measured in three different ways: average pod brightness, calibrated density, and percent of the surface area covered by discoloration. A Hunter colorimeter was used to measure L-value. These measurements of discoloration were correlated with each other and with the weight percent of the pods considered as damaged by USDA inspectors.