Note. Sugar, Moisture Contents, and Color of Chestnuts during Different Storage Regimes

Abstract

Color, moisture and sucrose, glucose and fructose contents of chestnuts (Castanea sativa Mill.) at several initial states (whole and undried; whole, peeled, and partially air-dried, with or without prior sucrose treatment; peeled, broken, and undried or partially air-dried) were monitored for 11 months during storage under various conditions (unpacked, packed in plastic bags at ambient pressure, or vacuum packed) and temperature (at room temperature, 3°C or -18°C). Moisture content decreased considerably in all cases except in those of packed whole peeled chestnuts without sucrose treatment and stored at room temperature or 3°C. Chestnuts stored for 2 months in contact with the atmosphere had moisture contents of only ∼4% of their dry weight. After 4 months storage, sucrose content had fallen (in some cases to zero) in all samples except in broken chestnuts dried to a 2% moisture content and conventionally stored whole unpeeled chestnuts (in which sucrose content rose slightly). Glucose and fructose contents generally peaked after 1-2 months of storage, and by month 4 returned to initial or lower levels. Sugar content was hardly affected by initial moisture or sugar contents except when moisture content had been reduced to 2%. Color changes were least during storage in air or at 3°C.