LEUCOANTHOCYANIDIN OXIDATION IN PECAN KERNELS - RELATION TO DISCOLORATION AND KERNEL QUALITY

The red‐brown discoloration in the testa of pecan [Carya illinoensis (Wang) K. Koch] kernels appears to be caused by the oxidation of endogenous leucoanthocyanidins to phlobaphenes, cyanidin and delphinidin. Oxidation was progressive in kernels of the Stuart and Schley varieties during storage for 16 wk at 32°C, 50% RH. The levels of leucoanthocyanidins in the two varieties differed significantly, however, rates of transformation were not different. Correlations between weekly increases in these compounds and peroxides formed in the pecan oils were low. Changes in peroxide values and Hunter values correlated well; thus, total color change of the testa may be a useful index of lipid quality. Differences between varieties in quantities of phenols suggest the influence of these compounds on the stability of pecan kernels. Copyright © 1978, Wiley Blackwell. All rights reserved