Physiological and Biochemical Responses of Banana ‘Prata-Anã’ Subjected to Hydrothermal Treatment

Abstract

Objective: The objective of this study was to assess the effect of hydrothermal treatment applied to banana ‘Prata-Anã’ before refrigerated storage.
 Study Design: The employed experimental design was the completely randomized type (CRD) and composed of 4 repeats with 4 fruits, in a 5 x 4 +1 factorial scheme, with five storage days (days 1, 2, 3, 4 and 5) at 25°C after removal from the refrigerated chamber, four immersion temperatures and one control (fruits without hydrothermal treatment).
 Study Location and Duration: The experiment was conducted in the Post-Harvest Physiology Laboratory of the State University of Montes Claros between March and June 2017.
 Methodology: The bananas were harvested and separated into 4-fruit bouquets, which were immersed in water at 50, 52, 54 and 56°C for 2 minutes; fruits without hydrothermal treatment were used as control. Each bouquet was placed in polyolefin membrane packs that were then contained in boxes and stored in chambers at 10oC and RH of 80% for 25 days. After the 25 days, the fruits were taken out of the chamber and stored at 25oC. During the 25oC storage, physical and chemical analyses were performed.
 Results: On the day of removal from the refrigerated chamber, all bananas, regardless of treatment, presented a yellowish color. The temperature of 56oC resulted in greater fresh mass loss and higher solute extravasation values. Lower chilling index values and higher vitamin C values were found as the immersion temperature increased.
 Conclusion: The full ripening process of banana ‘Prata-Anã’ occurred after removal from the refrigerated chamber in all hydrothermal treatments and with lower chilling index values.