Modified-atmosphere packaging of blueberry fruit: modeling respiration and package oxygen partial pressures as a function of temperature.
1994
Cameron A.C. | Beaudry R.M. | Banks N.H. | Yelanich M.V.
A mathematical model was developed to characterize the interaction of fruit O2 uptake, steady-state O2 partial pressures in modified-atmosphere (MA) packages and film permeability to O2 (Po2),) from previously published data for highbush blueberry (Vaccinium corymbosum L. 'Bluecrop') fruit held between 0 and 25C. O2 uptake in nonlimiting (Ro2maxT) and the [O2]pkg at which O2 uptake was half-maximal (K1/2T) were both exponentially related to temperature. The activation energy of O2 uptake was less at lower [O2]pkg and temperature. The predicted activation energy for permeation of O2 through the film (EPo2, kJ.mol-1) required to maintain across the range of temperatures between 0 and 25C was approximately 60 kJ.mol-1. Packages in which diffusion was mediated through polypropylene or polyethylene would have Eapo2 values of approximately 50 and 40 kJ.mol-1, respectively, and would have correspondingly greater tendencies for to decrease to excessively low levels with an increase in temperature. Packages that depend on pores for permeation would have an EaPo2, of < 5 kj.mol-1. Our procedure predicted that, if allowed to attain steady-state conditions, packages with pores and optimized to 2 kPa O2, at 0C would become anaerobic with as little as a 5C increase in temperature. The results are discussed in relation to the risk of temperature abuse during handling and marketing of MA packaged fruit and strategies to avoid induction of anaerobiosis.
显示更多 [+] 显示较少 [-]