Phenolic composition, browning degree and enzyme activities of important Turkish apricot cultivars as influenced by harvesting year and ripening

Abstract

Phenolic content, browning degree, enzyme activities (polyphenol oxidase (PPO), pectin methylesterase (PME) and β-glucosidase) of three apricot varieties of Malatya region of Turkey were assessed during ripening on trees over two years. All measured variables varied across the cultivar, ripening stage and year. Both individual and total phenolic contents (TPC) decreased with ripening in all the cultivars studied. The activity of PPO, PME, and β -glucosidase continuously decreased with ripening in both harvest years. In all varieties browning degree decreased with ripening. It was observed that the greatest browning was in Hacıhaliloğlu cultivar at all ripening stages. Significant differences (p