PURPOSE: When green vegetables are refrigerated under illumination, these vegetables are tightly packaged with a high-transparency or translucent film of high gas barrier property under vacuum or replacement with an inert gas, to prevent the discoloration.

CONSTITUTION: On the refrigeration of green vegetables containing chlorophyll such as green pea or spinach under light illumination, these vegetables are packaged with a transparent or translucent film with an oxygen permeability of less than 40cc/ m2.24hr atm. at 27°C and 65% RH and the inside of the package is evacuated with a vacuum of at least 750mmHg so that the oxygen concentration in the package comes down to less than 0.5vol% or replaced with an inert gas such as nitrogen or carbon dioxide, then the package is tightly sealed.