HEAT SHOCK REDUCES BOTH CHILLING INJURY AND THE OVERPRODUCTION OF REACTIVE OXYGEN SPECIES IN YELLOW PITAYA (HYLOCEREUS MEGALANTHUS) FRUITS

• Published in: Journal of food quality Vol. 34; no. 5; pp. 327 - 332
• Main Authors: NARVÁEZ-CUENCA, CARLOS-EDUARDO, ESPINAL-RUIZ, MAURICIO, RESTREPO-SÁNCHEZ, LUZ-PATRICIA
• Format: Journal Article
• Language: English
• Published: Malden, USA Blackwell Publishing Inc 01.10.2011
• Subjects: Chilling; Cooling; Fruits; Heat shock; Injuries; Injury prevention; Refrigeration; Shelf life
• ISSN: 0146-9428; 1745-4557
• DOI: 10.1111/j.1745-4557.2011.00398.x

ABSTRACT Yellow pitaya fruits were heat‐shocked (25C/24 h), stored at 2C for 14 days and then held for 13 days at 18C. Chilling injury (CI), respiration rate, hydrogen peroxide (H2O2), superoxide anion radical (O2•‐) and lipid peroxidation product (LPP) levels were measured. Pitting and browning were detected in the control fruit when moving from 2 to 18C. Minor CI symptoms were found in the treated fruit. There was a rapid increase in the levels of H2O2, O2•‐ and LPP in the control fruits when moved to 18C. At the end of the storage, the levels of these compounds were 4.5‐, 4.9‐ and 6.2‐fold higher, respectively, in the control than in the treated fruit. The results suggest that the reactive oxygen species levels in the heat‐shocked fruit were adequate for normal ripening, while the levels in the control group were excessively high, inducing CI symptoms. PRACTICAL APPLICATIONS Refrigeration is a technique that can be used to extend shelf life of yellow pitaya fruit. Nevertheless, these fruits are susceptible to chilling injury. This research was developed to study the effect of heat shock treatment on the preservation of whole yellow pitaya fruit during refrigeration. Preheating fruit at 25C for 24 h before storage at 2C for 14 days prevented chilling injury during shelf life at 18C. Thus, the combination of heat shock and refrigeration delays the senescence of yellow pitaya fruit and therefore improves its shelf life. Furthermore, this treatment could be useful during quarantine treatments of fruit fly‐infested fruit.