Postharvest conservation of peaches with the use of edible coatings added with yerba mate extract

Abstract

The present study had the objective of verifying the potential of the application of cassava starch-based coatings (F), supplemented with yerba mate extract (E) (Ilex paraguariensis St. Hill) in the postharvest conservation of peaches. The fruits used were peaches cv. Della Nona and the applied treatments were: uncoated fruits, fruits with cassava starch-based coatings supplemented with yerba mate extract at concentrations of 0 g L^-1 (F + 0% E), 5 g L ^-1 (F + 5% E), 10 g L^-1 (F + 10% E) and 15 g L^-1 (F + 15% E). The fruits were stored for 10 days at 1 °C with 95% relative humidity. To evaluate the postharvest quality of fruits, physicochemical analysis was performed, including soluble solids, titratable acidity, weight loss, and firmness. To evaluate the in vitro effect of the coatings on fungus growth Monilinia fructicola, the causal agent of brown rot, conidia germination and the area under the mycelial growth curve were evaluated. In order to evaluate the in vivo brown rot control, the fruits were inoculated with the M. fructicola fungus and evaluated for incidence (%) and infection index (%) and the peroxidase and polyphenol oxidase enzymes. The use of coatings reduced the loss of fruit mass by 50%, an increase of soluble solids content and improved the red color of the fruits, making them more attractive to the consumer. In addition, there was an increase of peroxidase enzyme activity in coated fruits and the coating treatment with 15% of yerba mate inhibited the development of brown rot in peaches.

Keywords:
Prunus persica; Edible coating; Ilex paraguariensis; Brown rot