ABSTRACT
Lychees are perishable fruits, and the application of ozone is a promising technology to preserve their quality. This study aimed to determine the effects of ozone gas and ozonated mist on the physicochemical properties of lychees. Two assays were performed using ozone gas and ozonated mist. The experiments were performed using a split-plot scheme, in which the plots corresponded to the treatments (ozone concentration or exposure time) and the subplots to the storage time, following a completely randomized design with three replicates. In the first experiment, ozone gas concentrations were tested (10 and 20 mg L-1) at exposure times of 15, 30, and 45 min. Corresponding control treatments included fruits that were non-exposed to ozone gas. In the second experiment, an ozone concentration was set (20 mg L-1) for exposure times of 3, 5, and 7 min. Exposure to ozone-free mist for 3, 5, and 7 min and control treatment were performed. The quality parameters of lychee fruits were assessed immediately after treatment (day 0) and on days 2, 4, 6, 7, and 8. Ozone gas was more effective for postharvest preservation of lychee than ozonated mist. Ozone gas was also proven to be more efficient than ozonated mist in maintaining the color of lychee peels. The effects of ozone gas and ozonated mist on pulp characteristics (Dif*, h*, and C*) were similar. Ozonated mist is recommended for vegetable species with an outer waxy cuticle or a high tolerance to water.
Key words:
Sapindaceae; Litchi chinensis Sonn.; fruit storage; ozone sanitization; physicochemical analyses
HIGHLIGHTS:
Ozone gas preserves the external appearance of lychee better than ozonated mist.
Ozone gas and ozonated mist preserve physicochemical characteristics of lychee pulp.
Ozonated mist treatment has the potential for postharvest fruit preservation.