Atmospheres with high levels of O2 can maintain the quality of vegetables and reduce microbial growth. The aim of this study was to evaluate the quality of 'Oso Grande' strawberry under controlled atmosphere with various O2 concentrations. Strawberries were selected, air-cooled and stored at 10ºC in hermetic mini chambers where O2 concentrations (1, 3, 20, 60 and 90%) were applied continuously at 150 mL min-1 for 10 days. Fruits were analyzed every 2 days. The lowest decay incidences were observed in the treatments with 90% of O2 (3% of fruits) and 60% of O2 (6% of fruits). Fruit from these treatments also had higher appearance ratings, which indicates preservation of fruit quality. Other treatments exhibited 16 to 20% of decay. The fruit respiratory rate stored at 1 and 3% of O2 concentration was 11.3 and 15.3 mL CO2 kg-1 h-1, respectively. Fruit treated with 20, 60 or 90% of O2 had similar respiration rates (21 mL CO2 kg-1 h-1), which were significantly higher than fruit treated with lower O2 concentrations. Acetaldehyde and ethanol levels did not increase during storage. Pulp firmness did not vary among treatments. Strawberries subjected to 60% of O2 maintained adequate levels of titratable acidity and ascorbic acid during the storage; however ascorbic acid decreased in all other treatments. Strawberry external color varied slightly depending on O2 concentration; however, these differences were not visually perceptible. 'Oso Grande' strawberries stored at 10 ºC under controlled atmosphere with 60 and 90% of O2 preserved the appearance and reduced decay, when compared to the other treatments.
Controlled Atmosphere; Oxygen Control; Postharvest; Fragaria x ananassa
