Free Amino Compound Total Nitrogen and Dry Matter Content of Summer Potatoes During Growth in Southern Ontario

Abstract

The free amino compound profiles, total nitrogen and dry matter content of tubers from five summer potato cultivars grown at Harrow and Simcoe, Ontario were monitored for four weeks commencing 3 July, about 80 days after planting in an attempt to determine the contribution of these factors to differences and changes in chipping performance which could not be accounted for by tuber sugar levels. In general: 1) tubers of the best chipping cultivars contained more dry matter and less amino compounds and total nitrogen than the poorer chipping cultivars at each harvest; 2) growth location differences were noted for corresponding cultivars and harvests; 3) larger proportions of the more intense Maillard colour forming amino compounds were found in tubers of the poorer chipping cultivars; and 4) tuber amino compound and total nitrogen levels decreased, and dry matter contents increased over the harvest period. Thus, the level and distribution of amino acids and the total nitrogen and dry matter content of tubers may be important factors contributing to the intensity of chip colour.