Low ethylene and rapid CA storage of 'Gala' apples

'Gala' apples lose their quality very fast during the first six months of regular CA storage. Low oxygen and other complementary storage procedures can increase storage period and retain fruit quality. The prices of 'Gala' apples in Brazilian market increase significantly six months after harvest. The purpose of this work was to evaluate the effect of ethylene removing and rapid establishment of CA conditions on quality of 'Gala' apples and verify the possibility of prolonging storage period for up to eight months. Two experiments were carried out during 8.5 months (1995) and 8 months (1996) in low oxygen CA conditions with 3% CO 2 and 1%O 2 at 1°C. Low ethylene concentration (below 1 ppm) was maintained with potassium permanganate scrubber. Fruits were stored 24 h after harvest. On rapid CA treatment, pulldown was done after chamber closing and fruit reached 1°C after 12 hours. In regular CA, fruits were cooled down from 18°C to 1°C during 9 days and then pulldown was done simulating the procedure of commercial stores. After storage period plus 7 days shelf life, in both years, fruits from rapid CA and low ethylene storage were significantly firmer (66.6 and 68.9 N) than the fruits from rapid CA without ethylene removing storage (58.4 and 61.8 N). Low ethylene maintained also the fruits crisp, juicy with greener ground colour and with an excellent appearance and taste. Apples in regular CA (slow cooling and retarded pulldown) presented a very low firmness (46.3 N) and high incidence of rotted and broken down fruits. Rapid CA (rapid cooling and establishment of atmosphere) in comparison with regular CA retained higher fruit firmness. It mey be concluded that 'Gala' apples can be well stored during 8 months in low oxygen CA storage with ethylene scrubbing and with rapid establishment of CA conditions.