High-Pressure Impregnation of Foods: Technology and Modelling Approaches

Abstract

Impregnation of fruits and vegetables is an effective approach to enrich their porous texture with functional solutions. High-pressure impregnation (HPI) is a newly developing impregnation technique based on imposing a high hydrostatic pressure on porous media soaked in a liquid phase. HPI can provide a high mass intake within a considerably short time. This paper reviews the current development of HPI in terms of its applications in food processing. The current paper also emphasizes fundamental approaches that have been developed to characterize and model the mass transfer during HPI. Moreover, a systematic review covering the general background and theoretical basis of pressure-driven impregnation into porous media is provided, which is necessary for future research developments in this field. The HPI process has a considerably higher mass transfer yield than vacuum impregnation and osmotic dehydration. However, due to the existing challenges in monitoring the process parameters such as internal pressure profile and mass transfer, specific approaches have been developed and applied to model and characterize the process. Thus, the ability to model the process highly depends on obtaining enough knowledge about the physics of the flow into the porous matrix under high-pressure and fluid/solid interactions. It is expected that by development in understanding the process and modelling it, HPI will be a highly reliable, controllable, and efficient process to (pre)treat porous foods such as fruits and vegetables for various applications.