Determination of the CO2 mass diffusivity of egg components by finite element model inversion

With the aim to improve the technological properties and the product freshness maintenance, the conservation of eggs in saturated CO2 atmosphere has been proposed. In this research, to study the CO2 diffusion inside the egg, a numerical model was developed. This required a characterization of the involved materials, with particular reference to the mass diffusivity. The present paper proposes a method, based on just simple laboratory determination of average total CO2 concentration and on the inversion of a finite element model, to estimate the CO2 mass diffusivity in the thin albumen, thick albumen and yolk of hen eggs. The method does not require complex devices and looks susceptible to extension to other physical problems. The results showed that the values of mass diffusivity determined by inverse method (thin albumen: 1.8E−09 m2/s; thick albumen: 8.5E−10 m2/s; yolk: 1.6E−10 m2/s) are comparable to the data reported in the literature for similar materials. The simulated and experimental values of CO2 concentration appear to be in good agreement, particularly for the albumen.