Abstract
An empirical mathematical model of effective permeability of tube channels and a model based on enzyme kinetics principle for generating respiration rate of ‘Irwin’ mango (Mangifera Indica Linn.) were studied to create a modified atmosphere (MA) package for maintaining the quality during storage. The results showed that the effective permeability of tube channels of 3 to 9mm in diameter and 50 to 350mm in length varied from 7.8×10-6 to 91.0×10-6m3/h for O2 and 7.0×10-6 to 78.5×10-6m3/h for CO2. The multiplicative non-linear model adequately described the effective permeability to tube dimensions with coefficient of determination (R2) of 0.956 and 0.959 for O2 and CO2 permeability, respectively. The enzymatic model of respiration rate generated from 12 different gas compositions fitted the experimental data very well. The model package of a 0.0043m3 glass jar with 1.2kg sample (three mangos) using a tube channel of 50mm in length and 9mm or 11mm in diameter attained an equilibrium gas composition of 8.3-11.4%O2 and 9.6-14.7%CO2, and showed some improved quality retention within 21 days of storage, while the control fruits were not acceptable after 14 days of storage. The model packages significantly reduced the fruit weight loss and tended to reduce the decline in hardness, SSC and acidity, reduce the incline in pH, and there were no significant changes in visual appearance due to decay incidence. This result suggests that the use of tube channel would be suitable for MA storage of mango.
