Quality of ‘oso grande’ strawberries is affected by O2, CO2 and N2O concentrations during controlled atmosphere storage

Abstract

Consumers around the world appreciate strawberries for their taste. They have low calories and high concentrations of soluble fibers, vitamin C and flavonoids. This paper verified the combined effect of O2, CO2, and N2 O levels on ‘Oso Grande’ strawberries stored at 10° C, under controlled atmosphere (CA). Five different gas mixtures were used: 0.03 kPa CO2 + 20 kPa O2, 80 kPa N2 O + 20 kPa O2, 90 kPa O2 + 10 kPa N2, 60 kPa O2 + 40 kPa CO2, and 20 kPa O2 + 20 kPa CO2 + 60 kPa N2 O. The lowest incidence of postharvest decay was observed with treatment 20 kPa O2 + 20 kPa CO2 + 60 kPa N2 O, followed by 80 kPa N2 O + 20 kPa O2 and 90 kPa O2 + 10 kPa N2. The treatment 60 kPa O2 + 40 kPa CO2 induced an increase in the production of acetaldehyde and ethanol, and these levels were considered inadequatefor human consumption. The first factor, named senescence, displayed a positive correlation with soluble solids, luminosity, hue angle, firmness and incidence of decay. The second factor, named CA-induced injury, showed that total acidity correlated negatively with ethanol and acetaldehyde levels. Hierarchical cluster analysis indicated that strawberries stored under 80 kPa N2 O + 20 kPa O2 for 14 days more closely resembled the quality of fresh fruit at the moment of harvest. ‘Oso Grande’ strawberries stored at 10 ºC under 80 kPa N2 O + 20 kPa O2 and 90 kPa O2 + 10 kPa N2 were in better conditions, with no metabolic alterations, showing that these are the ideal storage conditions.