Chilling injury in pineapple fruit: Fatty acid composition and antioxidant metabolism

• Pineapples of the Queen-type were more susceptible to chilling injury than those of the Smooth Cayenne-type.
• No evidence was found for a correlation between the development of chilling injury symptom in the two pineapple types and fatty acid composition or fatty acid oxidation.
• The symptom was correlated with the metabolism of reactive oxygen species, as reflected in the total antioxidant capacity and the ascorbate peroxidase activity.

Chilling injury (CI) was investigated in fruit of pineapple (Ananas comosus) cv. Pattavia (Smooth Cayenne-type) and cv. Trad-See-Thong (Queen-type) stored at 10 °C for 21 days. We hypothesized that CI would be due to inadequate antioxidant response and/or membrane lipid composition. CI symptoms were only found in cv. Trad-See-Thong. Symptoms were correlated with an increase in ion leakage, with lower pulp total antioxidant capacity, determined by the FRAP method, and with lower ascorbate peroxidase (APX) activity. No correlation was found between CI symptoms and the concentrations of hydrogen peroxide or ascorbic acid. Additionally, no correlation was found between symptoms and the activities of superoxide dismutase (SOD) or catalase (CAT). Thiobarbituric acid-reactive substances (TBARS; indicative of fatty acid peroxidation), the membrane fatty acid composition, and the ratio of membrane saturated to unsaturated fatty acid also showed no correlation. It is concluded that the development of CI symptoms was correlated with reactive oxygen species metabolism, as reflected in total antioxidant capacity and APX activity, while no evidence was found for a correlation with membrane fatty acid composition or fatty acid oxidation.