Comparison of Fresh-keeping Effects of Different Modified Atmosphere Packaging on Fresh Winter Jujube

Objective The study is carried out to explore the effect of modified atmosphere packaging (MAP) on the preservation of fresh winter jujubes (the turning-red area of pericarp is more than 2/3).

Method The winter jujubes were treated with two different types of MAP (MP20 and MP30), with the microporous packaging as the control. Winter jujubes were stored under different package treatments at two temperatures (25 ℃ and 0 ℃) to study the changes of physiological activity and nutritional components during storage.

Result Winter jujubes could be stored at room temperature (0℃) for 15 days and at low temperature (15℃) for 90 days, compared with microporous packaging, both the decay rates of winter jujubes packaged in these two kinds of MAP bags were reduced by more than 20% at 25 ℃ and 0 ℃. MAP could also inhibit the respiratory intensity of winter jujubes, maintain the fruit hardness (> 1 000 g/cm²) and reduce the loss of nutrients.

Conclusion The air permeability and perspectivity of winter jujube MAP bags should not be too high. The oxygen permeability of MP30 bag is lower than 6 000 cm³/m²·d·atm, after 50 days of storage, combined with the respiration effect of winter jujubes, the gas in the package could be regulated and the concentration of 5% O₂ and 1.0%-2.0% CO₂ could be formed to reduce the physiological metabolism of winter jujubes. Compared with the microporous packaging, the fresh-keeping period of winter jujubes in MP30 packaging is prolonged by over 30 days, which has a better market prospect.