Pectin Changes in Ripening Cherry Fruit

Abstract

ABSTRACT Pectin solubilization was studied during ripening of cherry fruit. Pectic materials were isolated at specific stages during development. The proportion of alcohol‐insoluble‐material decreased on a fresh weight basis with ripeness, but increased per fruit. Pectic substances were divided into water‐, oxalate‐ and acid‐soluble fractions. The oxalate‐and water‐soluble part increased as acid‐soluble components decreased. Water‐ and acid‐soluble fractions contained many more neutral sugar residues than the oxalate‐soluble fraction. Changes in individual sugars indicated the major alterations were the degradation of galactan and the absence of arabinan solubilization in acid‐soluble pectic substance. Size exclusion chromatography showed absence of pectin depolymerization during ripening, indicating that fruit softening does not depend on pectin depolymerization.