Effects of Polypropylene Film Packaging and Shipping Containers on Quality Stability of Welsh Onion (Allium fistulosum L.)

Abstract

The effects of combinations of bi-axial polypropylene (OPP) film bags and shipping containers on the quality stability of Welsh onion (Allim fistulosum L.) were investigated under simulated or actual conditions. When the Welsh onion was stored at a low temperature with high carbon dioxide and low oxygen levels, the respiration rate was reduced, indicating an extension of shelf life. In actual transportation, there was only a small difference in the Welsh onion temperature between a foamed polystyrene container and the usual corrugated fiberboard container. The result suggests that both materials have almost the same holding temperature effect. In a simulated condition where the Welsh onion was sealed with roughly heat-sealed OPP film bags and then stored in the foamed polystyrene containers at 20°C, the carbon dioxide level increased while the oxygen level decreased because of the high gas-barrier ability of the foamed polystyrene. Moreover, the carbon dioxide and oxygen levels were suppressed at 8.8 to 10.1% or 2.6 to 3.4%, respectively, by using completely heat-sealed OPP film bags and ordinary corrugated fiberboard containers. These results indicate that both materials provide the optimal storage condition for Welsh onions.