Comparison of fruit maturation and quality of ‘Gala’ apple strains at harvest and after storage

Abstract

Abstract Strains of ‘Gala’ apples with highly red-colored skins have been planted in new orchards based on consumer interest and financial returns to the producers. The effect of somatic mutation may not be limited to change in fruit skin appearance. In this study, six ‘Gala’ strains were compared regarding fruit maturity and quality attributes at commercial harvest time and after 210 days in controlled atmosphere cold storage plus seven days shelf-life. Experimental orchards were established in three regions and fruit assessed over four seasons. The fruit skin red color area was highest in ‘Baigent’ and ‘Galaxy’, and lowest in ‘Royal Gala’ and ‘Imperial Gala’. Fruit of ‘Maxi Gala’ and ‘Gala Real’ had intermediate skin coloration among the six strains. There was no difference among the strains regarding the fruit weight, starch index, flesh firmness, soluble solid content (SSC), and titratable acidity (TA) at harvest, and flesh firmness, SSC and TA after storage. Fruit of the six ‘Gala’ strains were equally affected by physiological disorders (flesh browning, fruit cracking, calcium deficiency disorders and shrivel) and fungal diseases (external decay, core rot and Glomerella cingulata spot) during storage, indicating that they have similar storability. Only ‘Imperial Gala’ and ‘Royal Gala’ exhibited superficial scald, an unusual disorder for ‘Gala’ cultivar. Harvest management and potential economic impacts of highly red colored fruit of ‘Gala’ strains are discussed.