Emulsifying properties of α-lactalbumin after high pressure treatment and subsequent lactosylation

Abstract

The effect of high pressure (HP) (300 MPa 25 °C, 1 h) and subsequent lactosylation of alpha-lactalbumin (alpha-La) (50°C, 44% RH, 168 h) was investigated regarding to its functional properties. The degree of lactosylation was evaluated by means of furosine determination, and expressed as the number of blocked lysines, being very similar to the native form. Taking into account these values and the number of free amino acids, there was evidence of higher aggregation in the pressurised samples than in the native ones. In general, emulsifying properties improved by the use of high pressure prior to lactosylation but there was no correlation between emulsifing activity index (EAI) and surface hydrophobicity. Solubility was over 80 % in all cases.