Chemical and biochemical changes in prickly pears with different ripening behaviour.

Chemical and biochemical changes were studied in ripening prickly pears from three Opuntia morphospecies with different ripening behaviour: Naranjona (O. ficus-indica), Blanca Cristalina (Opuntia sp.), and Charola (O. streptacantha), of early, intermediate, and late ripening, respectively. At fullyripe stage (commercial maturity), Blanca Cristalina showed the biggest fruits, the hardest texture, and its pulp had the highest protein content. There were no significant differences among morphospecies in pH or total soluble solids in fully ripe fruits. The three species exhibited considerable levels of vitamin C, dietary fibre, and minerals such as calcium, iron, and zinc. Protein expression was analysed in pulp and skin from every species at physiological and commercial maturity. Some proteins appeared at both stages, while many others expressed differentially. This study evaluated prickly pear components important for human nutrition and health, and provided basic information on pricky pear ripening, with a view to its control and to improving shelf life.