PHYSIOLOGICAL-RESPONSES AND QUALITY ATTRIBUTES OF PEACHES KEPT IN LOW OXYGEN ATMOSPHERES

Peach (Prunus persica L., cultivar 'Fairtime') fruits were kept in air and in 0.25 or 0.02% O2 at 0 or 5-degrees-C for up to 40 days to study the effects of temperature and insecticidal low O2 atmospheres on their physiological responses and quality attributes. Exposure to low O2 atmospheres for 3 days reduced respiration and ethylene production rates and internal CO2 concentration, but slightly increased resistance to CO2 diffusion. The low O2 treatments delayed incidence and reduced severity of internal breakdown (chilling injury) and decay of the peaches stored at 5-degrees-C. Low O2 atmospheres did not significantly influence changes in skin color, flesh firmness, and soluble solids content, but retarded titratable acidity loss and pH rise. Ethanol and acetaldehyde accumulated in peaches kept in 0.02% O2 at 0 or 5-degrees-C or in 0.25 O2 at 5-degrees-C. The fruits kept in air or 0.25% O2 at 0-degrees-C for up to 40 days and those stored in 0.02% O2 at 0-degrees-C or in air, 0.25 or 0.02% O2 at 5-degrees-C for up to 14 days had good to excellent taste, but the flavor of the fruits stored at 5-degrees-C for more than 29 days was unacceptable.