This research was carried out to assess the effects of modified atmosphere packing (MAP) conditions on physicochemical quality preservation of cv. 'Laetitia plums'. Fruit were cold stored (CS; 21.0kPa O2 + 0.03kPa CO2), MAP [fruit sealed in a low density polyethylene film (LDPE, 40µm), without perforation], MAP with the addition of CO2 (10kPa) inside the package, and MAP with perforated film (diameter of perforations = 2.0mm). During cold storage, the treatments MAP, MAP with perforated LDPE film, and MAP with the addition of CO2 had mean partial pressures of 1.9kPa O2 + 15.2kPa CO2, 8.1kPa O2 + 9.6kPa CO2 e 4.1kPa O2 + 16.0kPa CO2, respectively. Plums stored under CS had the lowest values of flesh firmness and force for skin penetration (measured with a texturometer), as well as less developed skin red color and higher incidence of skin cracking when removed from cold storage. At removal from cold storage, the force for flesh penetration and for fruit compression (measured with a texturometer) was higher for MAP with perforated LDPE film. However, after four days under ambient conditions, there was no significant difference between MAP treatments for these attributes. Titratable acidity assessed at removal from cold storage was higher in fruit left under MA than CS. The incidence of decays was lower in fruit left under MAP with perforated LDPE film. Respiration was higher in fruit under MAP than CS when assessed at removal from cold storage, but not after four days at ambient temperature. 'Laetitia' plums exhibit a high incidence of flesh browning, and this disorder was reduced in fruit under CS and MAP with perforated LDPE film.
Prunus salicina; postharvest; flesh browning; quality
