Effect of controlled atmosphere, temperature and cultivar on sprouting and processing quality of stored potatoes

Three crisping potato cultivars. Record, Saturna and Hermes, were stored at 5 or 10 degrees C in gas mixtures of either 0.5% CO2 and 21.0% O-2 (control) or 9.4, 6.4, 3.6 or 0.4% CO2, all combined with 3.6% O-2. There was almost complete sprout inhibition, low weight loss and maintenance of a healthy skin for all cultivars stored in 9.4% CO2 with 3.6% O-2 at 5 degrees C for 25 weeks. When tubers from this treatment were stored for a further 20 weeks in air at 5 degrees C the skin remained healthy and they did not sprout. The fry colour of crisps made from these potatoes was darker than the industry standard, but when they were reconditioned, tubers of cv. Saturna produced crisps of an acceptable fry colour while crisps from the other two cultivars remained too dark. Reducing sugar levels were related to fry colour both after storage and after reconditioning. The other gas combinations and the controls did not have the same effect on sprouting and none of the controlled atmosphere treatments controlled sprouting at 10 degrees C.