ABSTRACT
32 33High-pressure (HP) treatment of milk and products is a novel processing technique during which the product is treated in a vessel of suitable strength at a HP. Under pressure, biomolecules obey the Le Chatelier-Braun prin ciple (i.e., whenever a stress is applied to a system in equilibrium, the system will react so as to counteract the applied stress); thus, reactions that result in reduced volume will be promoted under HP. Therefore, HP is considered an interesting alternative for milk heat pasteurization and possibly sterilization, because under HP conditions, microorganisms (vegetative cells) and certain enzymes are inactivated and fresh flavor, color, taste, and vitamins are only minimally affected (Anema et al., 2005). The technique offers several advantages: (1) preserved products with char acteristics similar to those present before processing, (2) homogeneity of treatment due to the fact that pressure is uniformly applied around and throughout the food product, (3) shelf lives similar to thermal pasteuri zation, while maintaining the natural food quality parameters (nutrients, flavor, and sensorial preservation). There is no doubt that HPP represents another interesting and promising dimension for dairy processing not only because it inactivates microorganisms but also because it provides oppor tunities for development of new “value-added” dairy products. The need for an alternative to thermal processing as the primary means of elimi nating pathogenic and spoilage microorganisms is substantial.
