Vol.:(0123456789) 1 3 Food Engineering Reviews https://doi.org/10.1007/s12393-021-09299-4 High‑Pressure Impregnation of Foods: Technology and Modelling Approaches Hamed Vatankhah 1  · Hosahalli S. Ramaswamy 1 Received: 21 June 2021 / Accepted: 26 October 2021 © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2021 Abstract Impregnation of fruits and vegetables is an efective 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 sys- tematic 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 feld. 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 profle and mass transfer, specifc 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 fow into the porous matrix under high-pressure and fuid/solid interactions. It is expected that by development in understanding the process and modelling it, HPI will be a highly reliable, controllable, and efcient process to (pre)treat porous foods such as fruits and vegetables for various applications. Keywords High-pressure impregnation · Porous media · Fluid fow · Darcy’s equation · Fick’s law Introduction High-pressure processing (HPP) is a non-thermal technique to achieve microbial destruction and enzyme inactivation in foods while still retaining its nutritional compounds and fresh-likeness attributes [1]. In industrial processing, the food is usually pressure treated at 300–700 MPa for 3–5 min at either room or refrigerated temperatures. HPP has been studied and reviewed in various food processing areas [2, 3]. The research and innovation regarding HPP applications have been dedicated to the biological responses of the veg- etative and pathogenic bacteria under high pressure [4, 5]. Furthermore, HPP research has been done on the efect of high pressure on the chemical structure of food components caused by protein denaturation, starch gelatinization, enzy- matic inactivation, etc. [6, 7]. The third research category focuses on the impact of high-pressure on physical qualities of food ingredients, such as rheological and textural proper- ties. [8–10]. Moreover, HPP imposes signifcant pressure on food sys- tems. Thus, it can lead to a fuid fow into the porous struc- ture under pressure whenever there is a multiphase system of porous biomaterials and liquid phases. This issue might signifcantly afect the fnal treated product. Also, one can consider using the fuid as a carrier of certain products and intentionally conduct certain fortifcations. In the past years, high-pressure infusion of acids, antioxidants, and frming agents have been investigated as a pre-treatment to other food processing techniques such as thermal processing [11–13]. The current paper presents an overview of studying the pressure-driven mass transport of fuids into porous bioma- terials focusing on fruits and vegetables. Moreover, detailed methodologies are described on ways to adopt fuid transfer * Hosahalli S. Ramaswamy hosahalli.ramaswamy@mcgill.ca Hamed Vatankhah hamed.vatankhah@mail.mcgill.ca 1 Department of Food Science and Agricultural Chemistry, McGill University, Macdonald Campus, Ste Anne de Bellevue, QC H9X3V9, Canada