A Further Study of β-Galactosidase Activity in Apples Ripening in Store

Apples (Malus domestica Borkh.) were ripened in 2% O2 at 3·3 °C. The loss of galactose residues from the cortical cell walls was initiated after 27 d although an increase in the β-galactosidase activity of the tissue did not occur until after 50 d. β-Galactosidase activity associated with the cell wall was determined using discs of cortical tissue. A substantial level of activity was observed prior to picking and subsequently during ripening of the apples in air.