Desenvolvimento e maturação de frutos de pitaia vermelha de polpa branca

Abstract

In Brazil, pitaya fruit cultivation has expanded, this is mainly due to its great commercialization and processing potential. Despite the expansion, the lack of information about fruits maturation and quality is one of the main barriers for its culture. Therefore, the objective of this research was to study the changes that occur during growth and ripening of pitaya fruits of white pulp, besides indicating their harvest point. In the first experiment, the complete development of fruits from the first days after the anthesis to fruits in senescence process was followed. In the second experiment, processes involved in fruits ripening stages were detailed to determine fruit maturity indices and indicate the ideal time to harvest them. Thus, in the first experiment analyses of physical, physical-chemical, and mineral characterization of fruits were carried out at different development stages (7, 14, 21, 28, 35 and 42 days after anthesis). While in the second experiment, physical, physical-chemical and correlation analyses were performed, at intervals of 28, 30, 32, 34, 36, 38, 40 and 42 days after anthesis, including all stages of fruit ripening. After analyzing the two experiments, it can be noticed that important characteristics are observed throughout fruits growth and ripening. In general, increases in yield, mass, soluble solids, and decreases in peel thickness, firmness and moisture are observed. Significant and important levels are found for human diet, with emphasis on nitrogen, potassium, calcium, manganese, iron and zinc. The color of peel changes from yellow-green in unripe fruits to intense red as they mature. Peel coloration as well as the visual appearance of the fruit can be used successfully in determining maturity indices of fruits and determining fruits harvesting time. The ideal harvest point, taking into account the organoleptic characteristics and visual aspects is around 34-38 days, when it reaches its physiological maturity. From the 40 days, fruits become less attractive visually, due to scales wilting and loss of the intense pink coloration of their peel, although until the 42 days they have enough internal quality to be consumed, and they can be used for processing.