Effect of Maturity Stage of Papaya “Maradol” On Physiological and Biochemicals Parameters

Nowadays, the worldwide increase in diseases has motivated consumers to increase the intake of fruits and vegetables, in response to various research reports indicating that these produces can help to prevent and control certain types of illnesses, due to their potentially high antioxidant properties. In this work the effect of the stage of ripeness of papaya (Carica papaya L) on the content of bioactive components and antioxidant capacity was evaluated. Papaya was selected based on its visual ripeness, classifying it in four stages of ripeness (R1, R2, R3 and R4). Physiological and physical-chemical analysis performed included polygalacturonase (PG) and pectin methylesterase (PME) activity, total phenolic content , antioxidant capacity (measured using DPPH, TEAC and ORAC assays), firmness, pH, titratable  acidity, total soluble solids, and color (L*, a*,  b*,  °Hue,  C). The antioxidant capacity decreased 27% in the R4 in DPPH and TEAC, while there was an increase in ORAC values (60.9%) respect to R1; PG activity increased as the stage of ripeness of papaya fruit increased from 8.14 (R1) to 22.48 U/gfw (R4). PME was affected in a similar manner with an activity of 0.5562 U/gfw, at the end of the storage. A high correlation between activity PG and softening of ripening papayas was observed. During this study it was observed that papaya experienced changes in firmness, which correlated with the activity of PG and PME enzymes, and with the increase in respiration and ethylene production. In regards to antioxidant capacity (measured using DPPH, ABTS and ORAC techniques) the various stages of ripeness showed very good antioxidant capacity, being higher in R1, which correlated with the higher content of phenolic compounds found in this same ripening stage.