Modified-atmosphere packaging of blueberry fruit: modeling respiration and package oxygen partial pressures as a function of temperature.
Cameron, A.C., Beaudry, R.M., Banks, N.H., and Yelanich, M.V.
Journal of the American Society for Horticultural Science. Volume 119, Number 3, May 1994. Pages 534–539.
1994
บทคัดย่อ
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 anaerobi