Oil Characteristics of Peanut Fruit Separated by a Nondestructive Maturity Classification Method

Abstract A nondestructive peanut pod maturity classification method, Pod Maturity Profile (PMP), based on visual examination of the color and structural characteristics of pod mesocarp after partial removal of pod exocarp, was used to separate freshly harvested peanut pods into maturity classes. The separations made nondestructively were compared with those made by a method involving the examination of internal pericarp and testa characteristics. The groups separated by the two methods were closely related. In oil from the PMP classes, color decreased, free fatty acid content decreased, iodine value remained approximately constant, and oven stability of the extracted oil increased with increasing maturity. Total oil contents and fatty acid profiles had consistent but more complex relationships with maturity. The data indicate that the PMP method allows consistent and reproducible classification of peanut fruit maturity.