Identification of variables correlated with chilling injury in Pitahaya (Hylocereus undatus Haworth)

Abstract The pitahaya (Hylocereus undatus) is highly perishable and susceptible to chilling injury (CI) The objective of this study was to measure a set of biochemical, physiological, physical-chemical and physical variables in gradually chilling injured pitahaya fruits and assess the degree of correlation of each one with this damage. Pitahayas were stored at 2 or 7±1 °C and 90±6 % RH for up to 30 d, and then held at 22±4 °C and 60±8 % RH for up to 7 d. A visual evaluation of CI was conducted using a five point hedonic scale after storage and transfered to 22 °C. Titratable acidity (TA), total soluble solids, TSS/TA ratio, superoxide dismutase activity (SOD), glutathione activity (GR), piruvate decarboxylase (PDC), alcohol deshydrogenase activity (ADH), weight loss, ethanol content, electrolyte leakage (EL), translucency, hue, chroma, and firmness were analysed in fruit samples. Of which, TA, SOD, ethanol content, EL, and translucency were positively correlated with CI (rs=0.61, 0.65, 0.53, 0.83, and 0.68).