Prospective of modified atmosphere methods in preserving quality and storability of some Libyan soft dates

This paper reports the potential of using modified atmosphere (MA) for extending shelf-life and maintaining quality of soft dates at balah and rutab stages. First, MA of 10, 15 and 20% CO₂ each with 5% O₂ were applied at 1±0.5°C for storing ‘Hellawi’ and ‘Hurra’ dates palatable at balah stage. MA treatments were significantly different from regular air (RA) at 0.5 level; they extended shelf-life to12 weeks, maintained total soluble solids (TSS) and firmness, with no significant effects between MA treatment levels. However, MA treatments led to darker skin colour (L, a, b). They were significantly different from those measured at harvest. Second, 5 and 10% CO₂ with 5% O₂ were applied for keeping rutab of ‘Bronsi’ and ‘Taboni’ cultivars at 1±0.5°C, naturally and artificially ripe fruits were used. MA treatments led to extending shelf-life of both cultivars to 12 weeks, no significant difference among MA and ripening method were recorded in colour, firmness and taste at 0.05 level. Contrarily, RA treatment lasted for less than 4 weeks. Third, ≤5% CO₂ and O₂ were applied at 1±0.5°C for keeping dates of ‘Deglet’ cultivar at three ripening stages, fully ripe, partially ripe and dry. MA treatment was compared with freezing at -18°C and RA. Results showed comparable effect of MA treatment with freezing, but different from RA in colour, taste, and sensory parameters after 24 weeks. The reported findings enlightened the potential use of ≤5% CO₂ and O₂ at near 0°C for maintaining quality and extending shelf-life of dates at balah and rutab stages. MA tested conditions have shown good potential in packaging, transportation and storage of soft dates.