Pulsed vacuum brining (PVB) of meat products in salt-concentrated solutions gives rise to hydrodynamic mechanisms that facilitate solution infiltration into the meat structure. Previous studies have shown that these mechanisms can only function with porous structures. The estimated apparent porosity of meat is 1.69% (v/v). The difference in total pressure is the key to efficient infiltration-it forces occluded and/or dissolved gases from the meat during vacuum processing and then, upon the return to atmospheric pressure, solution infiltrates the pores from which the gases were expelled. Transfers between the occluded solution and the inner surfaces of the meat pores then occur within the product throughout brining under atmospheric pressure conditions. The solution is expelled again from the product in the next vacuum cycle. During PVB of poultry meat, solution infiltration and internal transfer account for respectively 9-22% and 7-17% of the salt gain obtained with this process. (C) 2003 Elsevier Science Ltd. All rights reserved.