Use of controlled atmospheres and heat treatment to maintain quality of intact and minimally processed green onions
G. Hong, G. Peiser and M. I. Cantwell
Postharvest Biology and Technology Vol: 20 Issue: 1Pages: 53-61.
2000
บทคัดย่อ
To maintain high quality and to extend the shelf life of intact and minimally processed (removal of roots and compressed stem) green onions (Allium cepa×A. fistulosum), the potential benefits of controlled atmospheres (CA) and heat treatment were evaluated. Atmospheres of 0.1¯0.2% O2 or 0.1¯0.2% O2 containing 7.5¯9% CO2 were the CA conditions that best maintained the visual appearance and prolonged shelf life to more than 2 weeks at 5°C in both intact and cut onions. No CA treatment completely controlled extension, growth or `telescoping' of the inner white leaf bases of the minimally processed onions at 5°C. Heat treatment (55°C water for 2 min) of the white leaf bases effectively controlled `telescoping' of cut onions stored at 5°C. Total soluble sugars generally decreased in intact and minimally processed green onions, but were maintained in heat-treated cut onions. Heat treatment did not affect thiosulfinate concentrations during 14 days at 5°C, except for treated cut onions not stored under CA.