Modelling O-2 and CO2 exchange for development of perforation-mediated modified atmosphere packaging

Perforation-mediated modified atmosphere packaging relies on the use of mac ro perforations or tubes to control the O-2 and CO2 exchange and create the desired atmosphere inside an otherwise gas-tight package. In this work, th e O-2 and CO2 exchange through a single tube was studied. Different tempera tures (5-20 degrees C) and tube dimensions (length from 9 to 17 mm and diam eter from 6 to 30 mm) were tested. O-2 and CO2 mass transfer coefficients w ere determined according to a lumped mass transfer capacitance model that y ielded a good description of the gas transfer. Temperature in the range tes ted did not show a significant effect on the mass transfer coefficients. A multiplicative non-linear equation was found to yield a good prediction of the dependence of the O-2 mass transfer coefficient on tube diameter and le ngth. The ratio between the CO2 and O-2 mass transfer coefficients, an impo rtant parameter in the design of MAP, was 0.81 and none of the factors test ed influenced its value. (C) 2000 Elsevier Science Ltd. All rights reserved .