Modeling and simulation of fermented sausages ripening with a heterogeneous porous media approach

This paper presents a mathematical model of fermented sausage drying, which relies on an innovative description of the sausage as a heterogeneous material, i.e., separately made of fat and lean meat, and a porous medium. The fat is considered as an inert matter dispersed in the meat matrix, while the lean meat is a porous medium in which the transport phenomena of water take place to the outside of the matrix during the ripening process. The implementation of the mathematical model in a Comsol Multiphysics®4.3 software code, the exploitation of the code outcomes and the validation of the code predictions are discussed against the results collected from a closely monitored and controlled batch production of "Salsiccia dolce", a typical meat product of Calabria region, at the Dodaro factory within the recent PON01-01409 "Safemeat" project. The "transport in porous media" physics was invoked in Comsol Multiphysics®4.3 and a semi-empirical correlation was adopted from literature for the capillary diffusivity as a function of the local moisture content and temperature. The simulation outcomes are discussed in terms of weight loss as well as space&time mapping of moisture in sausage, compared to the experimental measurements and to the results previously obtained by following a homogeneous model approach. The present results show an excellent agreement with the experimental data and an improvement with respect to the previous homogeneous model.