Some effects of gamma radiation on several varieties of Tasmanian potatoes. 2. Biochemical changes

Abstract

Tasmanian Up-to-date, Kennebec, Sebago, and Sequoia tubers were treated with low doses of gamma radiation to inhibit sprouting and were subsequently stored at 68¦F or 45¦F. Tubers were examined at bi-monthly intervals for some, or all, of the following biochemical constituents : dry matter, thiamin, reduced ascorbic acid, dehydroascorbic acid, total ascorbic acid, soluble reducing sugars, sucrose, total sugars, and starch. Radiation, independent of dose level, led to lower dry matter contents in the Up-to-date, Kennebec, and Sequoia tubers after four months storage, and in the Sebago tubers after six months storage at 68¦F, but not at 45¦F, when compared to the controls. The thiamin content of Up-to-date tubers w-as not influenced by radiation (16,000 rads). Storage w-as a more important factor than radiation in altering the ascorbic acid content of tubers. Radiation maintained, or even increased the normal level. Radiation increased the soluble reducing sugar content of Sequoia tubers, the total sugar of Sequoia and Sebago tubers, and the sucrose content of the Sebago tubers, but had little effect on the starch content of these varieties. Storage influenced some of these constituents, particularly in the Sebago variety.