Effects of current storage conditions on nutrient retention in several varieties of potatoes from Tenerife

The evolution of moisture, starch, amylose, ash, fructose, sucrose, glucose and ascorbic acid was studied in five cultivars of Tenerife potatoes in order to evaluate their variation during storage at 12 °C and 90% humidity. Differences in behaviour were detected among cultivars in relation to the period of storage under these conditions. The Negra cultivar presented the worst behaviour in storage, while the Bonita and Colorada cultivars presented the best. The moisture remained constant for the first 6 weeks; afterwards; a significant decrease was observed. A progressive decrease of starch (dry basis) over the time of storage was detected, while an increase of reducing sugars occurred. The amylose/amylopectin ratio increased during the first 6 weeks of storage. The concentration of vitamin C decreased markedly during the storage, and, after the 20th week, the content had decreased by more than 50%.