Quality variables of “Hass” avocado stored in modified atmosphere packaging

Abstract

Modified atmosphere packaging and refrigeration of fruits and vegetables are used to extend their shelf life. The objective of this research was to evaluate quality variables in avocado (Persea americana Mill.) cv. "Hass" during storage in modified atmosphere packaging (MAP) at 8 °C and contrast them to those obtained during storage at room temperature (RT) and refrigeration (REF). Fruits at physiological maturity were stored in MAP bags with a thickness of 0.20 mm. A completely randomized design was used; factors were: type of storage (RT 21 °C, REF 8 °C, and MAP 8 °C), storage time (8, 16, 24, and 32 days), and ripening time after storage (2, 4, and 6 days). Quality variables were firmness (penetration force), total color difference (ΔE) in exocarp and mesocarp (colorimeter), pH (potentiometry), and total soluble solids (TSS, refractometry). Avocados stored in MAP maintained (p > 0.05) firmness, which was higher compared to REF and RT during the storage period. Firmness retention for avocados at RT, REF, and MAP, at day 16, was 5.7, 32.6, and 87.2%, and at day 32, it was 0 (no reading), 9.5, and 78.2%, respectively. Total color difference in exocarp and mesocarp, pH, and TSS ranged from 3.8 to 25.6, 3.2 to 20.3, 6.7 to 7.1, and 5.3 to 7.7 °Brix, respectively. During the storage period, fruits stored at MAP showed a firmness, ΔEexocarp, and ΔEmesocarp similar to those of fresh fruit. Type of storage showed no effect on pH and TSS during the storage period. The package for modified atmosphere at 8 °C allows to prolong the shelf life of “Hass” avocado for a period twice as long as that at room temperature, based on the fact that changes in firmness and color are reduced, properties that are important quality benchmarks.