Efeitos do ácido salicílico e da radiação UV-C, isolados e combinados, na conservação pós-colheita de morangos BRS DC25 Fênix

Abstract

The strawberry (Fragaria x ananassa Duch.) is a fruit of high commercial value, but it has high postharvest perishability, due to its intense respiratory activity and susceptibility to spoilage fungi, such as Botrytis cinerea. Salicylic acid (AS) and ultraviolet C radiation (UV-C) are technologies studied separately as physical and physiological alternatives to extend the shelf life of fruits, but there is a lack of studies on their combined effect, especially in the national cultivar BRS DC25 Fênix. The objective of this study was to evaluate the effects of AS and UV-C radiation, applied in isolation and combination, on the postharvest conservation of strawberries of this cultivar. The fruits were subjected to six treatments, combining two concentrations of AS (2 mM and 3 mM) with or without exposure to UV-C radiation (dose of 2.40 kJ/m², 30 cm away from the emitting source), and stored at room temperature for 15 days, with evaluations carried out at times 0, 5, 10 and 15 days. The parameters of titratable acidity, pH, total soluble solids, color (L*, a*, b*) and total phenolic compounds were analyzed. The results showed that the titratable acidity and pH were not significantly influenced by the treatments, varying mainly as a function of the storage time. The total soluble solids showed greater stability in the UV-C treatments (T4, T5 and T6) compared to the control. The total phenolic compounds remained at higher levels only in the combined treatment of 2 mM of AS with UV-C (T5), while the other treatments showed a significant decrease during storage. UV-C radiation caused a temporary reduction in luminosity and red chroma at the time of application, an effect that disappeared in later times. It is concluded that the combination of AS and UV-C, specifically the T5 treatment, is the most consistent strategy for the maintenance of attributes related to the flavor and antioxidant capacity of BRS DC25 Fênix strawberries during storage, although its benefits do not extend uniformly to all quality parameters evaluated.