High‐Pressure Enhanced Infusion: Influence of Process Parameters

High‐pressure processing (HPP) has been shown to enhance infusion of small‐size molecules into foods primarily because of cell membrane rupture. The enhanced infusion has been previously explained using increased effective diffusivity, which does not elucidate the actual mass transport mechanisms. This study evaluates and explains the role of transport processes and the influence of process parameters on enhanced infusion of antioxidants by HPP. Frozen‐thawed cranberries were infused with quercetin. A greater amount of quercetin (three times) was infused faster (18 times) in cranberries after HPP (100 MPa–551 MPa at 22C) compared with those infused at ambient conditions. While freeze‐thawing process ruptured cell membranes in cranberries, measured as cell permeability, there was no additional cell rupture after HPP. A similar degree of measured cell permeability before (0.48 ± 0.01) and after HPP (0.48 ± 0.04), and observed enhanced infusion under high‐pressure suggest that cell membrane permeabilization may not be the only cause for high–pressure‐assisted infusion. PRACTICAL APPLICATIONS: Conventional diffusion‐based mass transport methods currently used in the food industry are slow processes. In order to accelerate the process, this research investigates (1) the potential of high‐pressure processing (HPP) to enhance and accelerate infusion in cranberries and (2) the mechanisms operative during high–pressure‐assisted infusion. The present study was focused on understanding influence of process variables on extent of infusion and cell permeability. HPP significantly enhanced and accelerated infusion of quercetin in cranberries. Additionally, the commonly accepted explanation of cell permeabilization being the only cause for enhanced infusion under high pressure was not found to be operative in the current system of study. The success of this research can highlight the potential of HPP as an alternative technology that will be useful to the food industry to develop a broad class of nutrient infused food products.