Storage of oriental bunching onions.
Li Wu;
Postharvest handling of fresh vegetables. Proceedings of a workshop held in Beijing, China, 9-11 May 2001
2001
บทคัดย่อ
Weight loss, visual quality, leaf discoloration and growing point extension are the major storage quality parameters for oriental bunching onion. With oriental bunching onions (cv. Zhangqiu) stored in the open air (30 to 40% relative humidity, RH) during winter, weight loss can be very high, sometimes greater than 50%. Temperature and relative humidity were the two most important limiting environmental factors affecting the storage life of oriental bunching onions. Weight loss, leaf discolouration and growing point extension were monitored over a range of storage temperatures (15, 5, 0, -1,-2, or -4 deg C) and humidities (95-100%, 70-80%, or 40-50% RH). Deterioration was more serious at 5 and 15 deg C than at 0 deg C. Temperatures of -1.5 deg C and -2 deg C were satisfactory for long-term storage, with leaves maintaining a good appearance for a further 7 days after withdrawal to 2 deg C. Appearance was better after storage at 95-100% RH than at 70-80% or 40-50% RH. A combination of low temperature and high relative humidity is ideal for storage of oriental bunching onions. Control of temperature with refrigeration is preferred, if economically feasible. Similarly, maintaining humidity to reduce moisture loss will improve quality. Simple methods for this range from use of film wraps to plastic sheets placed over shoots in bulk storage. Atmosphere modification (2-3% O2/1-2% CO2, and 5-6% O2/1-2% CO2) was more effective than air storage in extending the shelf life of oriental bunching onions. Growing point extension was also slowed by modified atmosphere storage.