Definition of harvest time and exogenous ethylene concentration in order to optimize the commercial potential and nutritional characteristics of bananas cv. Thap Maeo

Abstract

Bananas of the group Cavendish predominates in the world. However, the Brazilian domestic consumption is varied with different cultivars. Nevertheless, the biochemical and physiological information of the different cultivars consumed are still restricted and, the pre and postharvest treatments are often the same for all of them, compromising the fruit quality. Considering this, two points are fundamental to improve fruit quality: the definition of the harvesting time and the treatment appropriated with ethylene on fruit postharvest. Today, the harvest time is defined by the fruit diameter and the treatment with ethylene is the same for all cultivars. However, fruits with equal diameter are not always in the same stage of maturity, presenting different behaviors in post-harvest. Moreover, the treatment with ethylene is, commonly, made without any technical orientation. As a consequence of this lack of orientation, the fruits have poor quality and reduced shelf life. The Thap Maeo cultivar was chosen in this work for being resistant to the Sigatoka disease and Panama disease and also, because it differs from other cultivars in relation to carbohydrates contents and, therefore, can be marketed with the appeal "light", in relation to soluble sugars and finally, because of short shelf life of this cultivar. The goals of this work are: (i) establish the harvest time for the Thap Maeo cultivar using the sum of temperature which the plant was exposed during fruit development; (ii) establish the optimal concentration of exogenous ethylene to promote uniform ripening and sufficient shelf life for commercialization based on the physico-chemical characterization of the fruits and the levels of ethylene receptors; (iii) based on previous results, establish quality standards for this cultivar (color and texture of pulp and peel, sugar content, sensory analysis and analysis of volatile compounds involved in the aroma). (AU)