Effect of high-pressure treatment on structural properties of low density lipoprotein of hen yolk

PUPPO, M. C.; CHAPLEAU, N.; SPERONI, F.; DE LAMBELLERIE, M.; AÑÓN, M. C.; ANTON, M.

Montpellier, France

Congreso; ICEF9. International Congress on Engineering and Food. Congrès International de Gènie des Procedès Alimentaires; 2004

SOCIETE DE CHIMIE INDUSTRIELLE

Egg yolk is a proper ingredient for a great kind of food emulsions due to its good emulsifying properties. The low density lipoprotein (LDL) is an effective emulsifying agent with higher surface activity than that observed for whey proteins and casein. Surface properties could be improve by emergent technologies, therefore the objective of this work was to study changes in LDL structure due to HP treatment. LDL dispersions (1% w/v) of pH 3 and pH 8 (LDL3 and LDL8) were treated at pressures of  200, 400 and 600 MPa. Structure changes were analyzed by protein solubility (S), surface hydrophobicity (H0), free sulfhydryls (SHF), and circular dichroism (CD). Aggregation phenomenon of LDL was studied by size exclusion chromatography (SEC), quasi elastic ligth scattering (QELS) and native electrophoresis. Secondary structure changes followed by aggregation was observed for LDL8 at 600 MPa. This behavior was accompanied with a decrease in H0 and an increase in SHF. No effect on LDL3 structure with HP was observed.