Abstract
Changes in chlorophyll, carotenoid, ascorbic acid, and glutathione levels were determined during broccoli storage in 9 controlled atmospheres ranging from 0 to 10% O2 and 2 to 20% CO2 concentrations. In low O2 concentration, the level of glutathione decreased, whereas in high O2 and low CO2 concentrations, the level of chlorophyll and ascorbic acid decreased significantly. A mixture of 2% O2 and 4 to 10% CO2 was found to be optimum for simultaneous maintenance of pigments, ascorbic acid, and glutathione. Respiration models were developed as functions of storage time and O2 and CO2 concentrations using a multiple regression analysis based on these gas compositions. When the modified atmosphere gas environment inside a broccoli package was simulated, an optimum gas condition of 2% O2 and 5% CO2 was derived using a film having a 1, 000 ml/day/atm O2 transmission rate. Simulation result agreed well with experimental data.
