Gas Composition and Temperature Affect Quality of Fresh-cut Fennel
Freshly harvested bulbs of fennel (Foeniculum vulgare var. dulce) `Clio' were sliced at 5 °C, dipped in 100 mg·L–1 NaOCl solution, and packaged in passive modified atmosphere packaging (MAP) by using trays covered and thermal sealed with unperforated or perforated polypropylene film. According to common commercial needs a shelf life of 14 d at 0 and 5 °C was applied. The respiration rate of fresh-cut fennel was 1.3- to 1.7-fold higher at 5 °C than at 0 °C, and was 1.4- to 1.8-fold higher than that reported for whole bulbs. MAP did not prevent the declines in SSC and TA that occurred during storage, while pH did not change. Water loss was lower than 0.1% in all treatments, and no decay or physiological disorders developed during storage. The gas compositions of 16 to 18 kPa O2 plus 2 to 4 kPa CO2 generated within the perforated packages at 0 and 5 °C or 1.5 to 2 kPa O2 plus 18 to 20 kPa CO2 in unperforated packages at 5 °C did not inhibit browning on the cut surface or other sensory changes of the slices. However, atmospheres in unperforated packages of 4 to 6 kPa O2 plus 10 to 14 kPa CO2 at 0 °C maintained the sensory quality like at harvest.