Post-harvest maturity of avocados evaluated by non-destructive tests

Abstract

Flesh firmness in fruit depends on the maturity degree and it can be determined, in a destructive way, by measuring the required force to penetrate the fruit. However, important researches have been carried out in order to determine the maturity degree in fruits by non-destructive procedures. The objective of this work was to accomplish a comparative study between the mechanical parameters, resulting from controlled impacts and flesh firmness, and a traditional index, used in the evaluation of maturity in "Hass" avocados (Persea americana Mill.). Two batches of fruits were selected. One of them was not in contact with ethylene absorber, while the second one had a sepiolite absorber sachet which was smeared with KMnO4, in a dose of 9,5 g kg-1 per fruit. A computer assisted impact-testing device with a 49,29 g stem and a 0,04 m height was used. Impacts proved to be non-destructive under these conditions and therefore they could be used to determine the ripening stage in "Hass" avocado. The results were similar to both groups, although the one treated with the ethylene absorber presented a delay, making clear its effect on retarding the process of full ripeness in fruits.