Actualidad
Management to improve the postharvest life of sweet onion
Three intermediate day-length cultivars of sweet onions were lifted by hand when 70% of the necks of each cultivar had collapsed in 2009 and either: (1) field cured on the ground for two weeks and thereafter dried in a ventilated and heated store at 25?C for two weeks or (2) defoliated 8 cm above the bulb and dried at 25?C for four weeks. Subsequently the onions were transferred to a cold store and kept at
26 March, 2020
Redaccion
Poscosecha, postcosecha, postharvest, cebolla, onion, Allium cepa, cultivar, temperature, topping, defoliaci?n Three intermediate day-length cultivars of sweet onions were lifted by hand when 70% of the necks of each cultivar had collapsed in 2009 and either:(1) field cured on the ground for two weeks and thereafter dried in a ventilated and heated store at 25?C for two weeks or(2) defoliated 8 cm above the bulb and dried at 25?C for four weeks. Subsequently the onions were transferred to a cold store and kept at a temperature of 1?C and approximately 70% RH. In addition, one field-cured cultivar was stored at various storage-atmosphere conditions: (a) ambient atmosphere (20.9% O2 and 0.04% CO2),(b) ambient atmosphere enriched with 0.8 ppm ozone,(c) ambient atmosphere enriched with volatile mustard essential oil liberated from a 1% allyl isothiocyanate solution, or(d) controlled atmosphere (3% O2 and 5% CO2). The onions were evaluated three times with a three-week interval. The first evaluation took place 6-9 weeks after lifting. Compared to field curing, defoliation did not improve the storability of sweet onions. Defoliation increased the development of rotting. At the end of storage, 12-15 weeks after lifting, the proportion of onions discarded due to rotting increased to 29% in defoliated onions, but 17% in field-cured onions. In comparing various storage conditions, controlled atmosphere reduced the development of rotting resulting in 75% marketable onions measured 12 weeks after lifting compared to 56% marketable onions stored at ambient atmosphere. Sweet onions are softer and less pungent compared to long-day onions, and therefore, more susceptible to mechanical impact and fungal diseases, and this makes sweet onions only suited for short-term storage. Authors, original title and sourceSorensen, J.N. and Edelenbos, M. 2012. STORABILITY OF SWEET ONIONS IN RELATION TO DEFOLIATION AT HARVEST AND STORAGE ATMOSPHERES. Acta Hort. (ISHS) 969:183-188Abstract ISHS, Acta Horticulturae 969, VI International Symposium on Edible Alliaceae The image is by PROCECAM, onion grower association of Castilla La Mancha, Spain
