Effect of high-presure treatment on structure and emulsifiying properties of low-density lipoproteins from egg yolk

SPERONI, F.; MARIA CECILIA PUPPO; CASTELLANI, O. F.; CHAPLEAU, N.; LAMBALLERIE-ANTON, M.; AÑÓN, M. C.; ANTON, M.

Mar del Plata

Congreso; X Congreso Argentino de Ciencia y Tecnología de Alimentos. 1er Simposio Internacional de Nuevas Tecnologías; 2005

ASOCIACION ARGENTINA de TECNOLOGOS ALIMENTARIOS

High-pressure treatment represents a new method valid to improve the microbiological stability of agricultural raw materials that is sensitive to heat treatments. This is the case of egg yolk low-density lipoproteins (LDL), the main responsible fraction for the exceptional emulsifying properties of yolk. In this study, LDL dispersions in two pH conditions (3 and 8) were treated by high-pressure at 200, 400 and 600 MPa. Then, treated and non-treated solutions were studied and used to obtain oil-in-water emulsions. Some physicochemical characteristics of protein solutions like solubility, protein aggregation and protein denaturation, and some emulsifying properties like emulsifying activity and flocculation were studied. Protein aggregation and denaturation were drastically enhanced by high-pressure treatments at pH 8. At this pH value, emulsifying properties of treated LDL showed diminution of flocculation. So, at least at pH 8, high-pressure treatments improve LDL emulsifying properties.