Comparison of Chestnut (Castanea spp.) Quality Characteristics according to Storage Temperatures and Cultivars

This research was conducted for major cultivated chestnut (Castanea spp.) in Korea to compare chestnut quality characteristics according to storage temperatures (4 Celsius vs. -1 Celsius) and cultivars. Color, hardness, soluble solids content (SSC), rate of decay and sensory evaluation were investigated during 16 weeks storage. Cultivars Tsukuba and Ishizuchi showed the least pericarp color change while cultivars Riheiguri and Daebo showed the most pericarp color change during storage. Chestnut fruits stored at -1 Celsius showed less pericarp color change than those stored at 4 Celsius. Cultivars Arima and Tanzawa exhibited the decrease tendency of hardness with lowest hardness during storage at -1 Celsius. Chestnut fruits stored at 4 Celsius showed high hardness than those stored at -1 Celsius. Cultivars Riheiguri showed the highest increase of SSC, while cultivar Arima showed the lowest increase of SSC after 16 weeks of storage. The SSC increased in nuts from all cultivars at both temperatures, but nuts stored at -1 Celsius showed higher increases in SSC than nuts stored at 4 Celsius. Cultivars Ishizuchi and Riheiguri showed high rates of decayed nuts in contrast to cultivars Daebo, Okkwang and Tanzawa that showed low rates of decayed nuts during storage. The chestnut fruit stored at -1 Celsius showed less decay than fruit stored at 4 Celsius. Texture and sweetness were tested for sensory evaluation. Among the tested cultivars, Riheiguri, Daebo and Tsukuba showed hard texture and very sweetness, while Tanzawa showed relatively soft texture. Arima and Okkwang showed weak sweetness during storage. Nuts stored at 4 Celsius exhibited harder texture than nuts stored at -1 Celsius while -1 Celsius exhibited more sweetness than nuts stored at 4 Celsius. Chestnuts for hard texture and short-term storage (less than one month), 4 Celsius will be a proper storage temperature, while in order to store long-term (more than 4 month), -1 Celsius will be a proper storage temperature. Result from this study provide base-line data of postharvest management for Korean cultivated chestnut as well as contributing increased product value and income for chestnut producers.