Oxidative discoloration of potato tuber tissue related to translucency of processed dice

In 1965 and 1966 potato clones from Maine, New Jersey, Ohio and Wisconsin field tests were evaluated subjectively for the translucent appearance of processed dice in milk and were examined colorimetrically for the degree of oxidative discoloration. There was a highly significant positive correlation between discoloration and translucency. The effects of time and location were minimized by relating each clone to the values for Katahdin in corresponding plots. By setting arbitrary selection limits of 40% and 75% of the Katahdin mean optical density, it was found that the method could be used for either selection of low-translucency or rejection of high-translucency types. Values less than 40% were generally acceptable, greater than 75% unacceptable and intermediate values were inconclusive. A scheme is presented whereby this method, in combination with a soluble protein method, was applied to several clones.