CONTROLLED ATMOSPHERE STORAGE OF 'OPAL STAR' FEIJOA

Feijoas (Acca sellowiana) have a short harvest season and a limited postharvest life. In order for the New Zealand feijoa industry to export to distant markets a postharvest life of at least 6 weeks is required. Controlled atmosphere (CA) storage of ‘Opal Star’ feijoa fruit was evaluated as a means of extending postharvest life. Fruit quality changes were measured when fruit were stored in air or in four CA atmospheres (a matrix of two levels of oxygen (2 and 5 kPa) and two levels of carbon dioxide (0 and 3 kPa)) at 4°C for up to 10 weeks. Fruit weight loss during 10 weeks in CA at 4°C was 1.5-2% of initial weight. Firmness of fruit stored in air or in CA with 3 kPa CO₂ decreased from about 18 N at harvest to ~ 9 N after 10 weeks at 4°C. Firmness declined at a lower rate for fruit under CA conditions with 0 kPa CO₂ (~ 14 N after 10 weeks). Total soluble solids decreased as storage time and subsequent shelf life increased. Air stored fruit were less green (lower hue°) after 8 weeks storage. Individual fruit from all treatments, including fruit stored in air, developed an external discolouring injury after 6 weeks at 4°C. CA appears to offer some benefits for increasing the storage life of ‘Opal Star’ feijoa but further investigation is required to explore efficacy under commercial conditions.