title: The Combined Effect of High Hydrostatic Pressure and Calcium Salts on the Stability, Solubility and Gel Formation of β-Lactoglobulin.
abstract: Stability, aggregation and gelation of β-Lactoglobulin are affected by high pressure and salts of the Hofmeister series. Little is known about their combined effects on structure formation processes of β-Lactoglobulin, mainly because many salts of the series are not suitable for use in food. Here, we investigate the effect of calcium salts on the strength of pressure-induced gels, inspired by the fact that high pressure and salts change the water structure in a similar way. We find that the larger the applied pressures, the higher the strength of the gels. In addition to pressure, there is a significant influence by the type of anions and the amount of added calcium salts. Gel strength increases in the order CaCl₂ < Ca (NO₃)₂ < CaI₂. This trend correlates with the position of the salts in the Hofmeister series. The results are explained by analogy with the thermal aggregate formation by taking reaction rates for unfolding and aggregation, as well as specific/non-specific salts effect into consideration.
authors.affiliation: Chair for Food Process Engineering and Dairy Technology, Technische Universität München, 85354 Freising-Weihenstephan, Germany. daniel.saalfeld@tum.de.
authors.forename: Daniel
authors.initials: D
authors.lastname: Saalfeld
authors.affiliation: Chair for Food Process Engineering and Dairy Technology, Technische Universität München, 85354 Freising-Weihenstephan, Germany. ina.riegel@gmail.com.
authors.forename: Ina
authors.initials: I
authors.lastname: Riegel
authors.affiliation: Research Centre for Nutrition and Food Science (ZIEL)-Section Technology, Technische Universität München, 85354 Freising-Weihenstephan, Germany. ulrich.kulozik@tum.de.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Kulozik
authors.affiliation: Chair for Food Process Engineering and Dairy Technology, Technische Universität München, 85354 Freising-Weihenstephan, Germany. ronald.gebhardt@tum.de.
authors.forename: Ronald
authors.initials: R
authors.lastname: Gebhardt
keywords: Hofmeister series; gel formation; high hydrostatic pressure; β-Lactoglobulin