"Physicochemical and Functional Alterations of Low-density Lipoproteins from Hen Egg Yolk Induced by Isostatic High Pressure"

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

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Año: 2006 p. 1 - 3

1777-5566

High-pressure processing represents a potential technology to stabilize microbiologically yolk with less detrimental physicochemical and functional effects on yolk LDL. To test this possibility, high-pressure treatments have been performed on LDL solutions and their subsequent impact on LDL physicochemical and emulsifying properties have been assessed. LDL solutions (10 mg proteins / ml) at two pH levels (pH 3 and 8) were treated at different pressure levels: 200, 400, 600 MPa, at 20°C. LDL solution characteristics (solubility, aggregation and protein denaturation) and LDL emulsifying properties (oil/water 30:70 emulsions: droplet size, flocculation and protein adsorption), of non treated and high-pressure treated solutions were compared. High-pressure treatment of LDL solutions leads to some modifications of their physicochemical and functional characteristics, specially at pH 8. Particularly, protein denaturation and aggregation are enhanced at this pH by high-pressure treatment and the consequences of these modifications on LDL emulsifying properties are a significant decrease of depletion and bridging flocculations. However, these modifications do not influence the capacity of LDL adsorption at the oil-water interface as we have observed the same percentage of adsorbed proteins. In conclusion, a high-pressure treatment of LDL dispersions combined with an alkaline pH is not detrimental for the fabrication of oil-in-water emulsions and could lead to the generation of more stable emulsions.