The Effect of High Pressure Processing on Milk: An Overview

Abstract

High pressure processing (HPP) is a non-thermal processing technique or cold pasteurization technique used for preservationof different types of food products, due to its lethal effect on pathogenic and spoilage microorganisms, while causing minor effect on food quality and sensorial attributes. Thus, HPP is currently being applied to a variety of food products, especially fruits, vegetables, and meat products, but dairy industry has not implemented the technology yet. This overview presents firstly a brief description of the thermodynamic principles of HPP followed by a description of the high pressure effect on milk components. Generally, HPP treatment of milk in the range of 100–600 Mega Pascal has very significant implications for its constituents depending on pressure level, holding time and temperature. Pressure-induced changes of the milk characteristics includes inactivation of bacteria, disruption of the casein micelles, denaturation of whey proteins, and solubilization of minerals associated with the micelles. In addition, HP treatment of milk at higher temperatures generally increases inactivation of alkaline phosphatase.