Applications of vacuum impregnation as a technology to incorporate functional components in vegetal matrices

Abstract

Currently, the search for technologies that improve the biological activity, sensory and functional properties of foods has led to the application of vacuum impregnation (VI). This technology is based on the transfer of mass from a liquid medium to a porous matrix by means of pressure gradients, intensifying capillarity and flow diffusion. VI has a variety of applications in the food industry, particularly in the use of vegetable matrices; the main functional components (FC) used to impregnate come from polyphenolic extracts, vitamins, minerals and probiotics. The purposes for which they are applied may be to improve sensory properties, lengthen shelf life, improve the load of bioactive compounds, antioxidant capacity and creation of probiotic foods. However, there are several considerations in the use of VI, due to the many process variables that are involved, coupled with the fact that there are few studies that explore the interactions of the impregnated FC with the porous food matrix. This review article intends to summarize the theoretical principles of VI, studies of the application of this technology in vegetal matrices, the main FC that are used to impregnate, response variables evaluated after VI and the limitations and challenges that this technology presents.