Changes in Chemical Compositions and Enzymatic Activities During Fruit Ripening in Hawthorn (Crataegus Pinnatifida)

In this study, changes in some chemical compositions associated with fruit quality and enzymatic activities were investigated during ripening of hawthorn fruits from the 88th to 148th day after full bloom day (from August 11 to October 10, 2013). Significant differences in these indices were found between different maturation stages as well as hawthorn cultivars. During ripening of hawthorn fruits, the content of total soluble solids (TSS) and the reducing sugar (RS) increased continuously and progressively. The pH values of hawthorns first decreased significantly and then increased. The activities of polyphenoloxidase (PPO) and peroxidase (POD) in hawthorns decreased significantly during ripening. The catalase (CAT) and phenylalanine ammonia lyase (PAL) activity in Mopan hawthorns decreased significantly, while they first decreased significantly and then increased during ripening of Dajinxing hawthorns. The outcomes of this study provide additional and useful information for fresh consumption and processing as well as utilization of dropped unripe hawthorn fruits.