Determinação da atividade respiratória (CO2) em frutos de Juazeiro colhidos em cinco estádios de maturação

Abstract

<p>Juazeiro (Ziziphus joazeiro Mart.) is a prominent plant in the midst of adverse conditions in Caatinga. Its fruit is small, fleshy, sweet and very perishable and it has a white pulp. This condition induces a high rate of respiration to the fruit and, therefore, interferes with its ripening. Thus, the objective of this study was to determine the quality and respiratory activity (CO2) in Juazeiro fruits. Juazeiro fruit were harvested from plants located at the Center of Science and Agri-Food Technology, at the Federal University of Campina Grande, Campus Pombal-PB, and taken to the Laboratory of Chemistry, Biochemistry and Food Analysis . The fruits were selected for the absence of damage and classified in five stages of maturation, being evaluated for pH, titratable acidity, soluble solids, soluble sugars, ascorbic acid and respiratory rate. Stage IV maturation fruits were stored under controlled temperature (25±2 ºC and 34±1% RH) for 4 days and evaluated on all storage days for respiratory rate, loss of fresh weight, titratable acidity and soluble solids. The advancement of maturation resulted in sweeter, slightly more acid juazeiro fruits and with a subtle reduction in the concentration of ascorbic acid. The highest respiratory rate was obtained in stage III maturation fruits, indicating that until this stage of maturation the fruits did not reach their full maturity, being probably in the final stage of growth. Regarding storage, there was a peak in the respiratory rate with 2 days of storage, indicating that the Juazeiro fruits present a climacteric behavior, reinforced by the responses observed in soluble solids and titratable acidity.</p>