Sensorial Characteristics of 'Kumagai' Guavas Submitted To Passive Modified Atmosphere In Plastic Packages

摘要

Guavas CY .Kumagai fruits were packed in plastic bags and stored at 10°C and 85-90% RH during 7,14,21 and 28 days, followed by open ex- posure for 3 days at 25°C and 70-80% RH to simulate commercial handling con- ditions. The packaging materials used were: multilayer coextruded polyolefin film with selective permeability (PSP), low density polyethylene film (LDPE), LDPE film with mineral incorporation (LDPEm) and heat-shrinkable polyolefin film (SHR). Guavas without plastic packages were used as control samples. The concentrations of 0_2 and C0_2 in the package headspace and the sensorial charac- teristics of the guavas (skin color, pulp texture, off-flavor and overall quality) were evaluated. The LDPE film presented the higher gas barrier and promoted the lowest O_2 level (0.1 %) and the highest C0_2 concentration (19%) inside the packages. Such passive modified atmosphere induced both off-flavor and abnor- mal ripeness. The polyolefin heat-shrinkable film provided poor modification in the package atmosphere, so the fruits exhibited fast senescence (decay). The film incorporated with mineral provided an atmosphere of 3% O_2 and 4.5% C0_2 inside the packages,which kept the fruit with good sensorial characteristics for 14 days.The coextruded polyolefin film provided an atmosphere of 0.5% O_2 and 4.5% CO_2 that was sufficient to maintain the fruit with good sensorial characteristics for 28 days.