Gala’, 'Royal gala' and 'Brookfield' apples stored under ultra-low oxygen and two temperatures

Most apples produced in Brazil have to be stored for regular the supply to the consumer market throughout the year. Thus, the present study aimed to check the differential response of 'Gala', 'Royal Gala' and 'Brookfield' apples stored under different ULO and temperature conditions. The experiment had a completely randomized design with 25 fruits per experimental unit and a three-factor design (2x5x3) with split-plots. After eight months of storage plus seven days of simulated shelf life, there was a significant triple interaction among the factors temperature/CA/cultivar for enzyme 1-aminocyclopropane-1-carboxilate (ACC) oxidase activity, ethylene production, respiration rate and flesh breakdown. For flesh firmness, there was no interaction among the factors tested in the present study. However, the observation of the main effects of each factor shows that flesh firmness can be preserved more effectively at 1.0° than at 0.5°C. Temperature of 1.0°C promotes better storage condition due the high flesh firmness and low ACC oxidase enzyme activity of fruit after storage. The best ULO condition stay between 0.8 up to 1.0 kPa of O2 and 1.5 up to 2.0 kPa of CO2 that reduces the ACC oxidase enzyme and ethylene production. 'Brookfield' apples have lower storage potential because the high respiration rate and flesh breakdown.