Sugar content and dry matter in potatoes stored under fluctuating temperatures in non-refrigerated stores in Greece

Potatoes were stored in non-refrigerated stores in the Marmarini area (central Greece, altitude about 50 m) and in the Polymylos area (northern Greece, altitude about 900m). In Polymylos, the tubers (cvs Fina and Spunta) were harvested in October 1985 and stored until April 1986; the temperature in the store fluctuated between −1°C and 14°C (mostly between 3°C and 7°C). In Marmarini, the tubers (cvs Sebago and Spunta) were harvested in December 1985 and stored until April 1986; the temperature in the store fluctuated between 0°C and 18°C (mostly between 5°C and 10°C). Every 1–2 months tubers were analysed for dry matter (DM), total sugars (TS) and reducing sugars (RS). In Marmarini, a significant increase of TS and RS was found in both cultivars from December to January, followed thereafter by a significant decrease. In Polymylos, a continuous (from November to April) increase in TS and RS was observed in cv. Fina while in cv. Spunta the sugars increased only until January, followed thereafter until April by a significant decrease.