|
Titre :
|
Effect of l-carrageenan on flocculation, creaming, and rheology of a protein-stabilized emulsion
|
|
Auteurs :
|
E. Dickinson ;
K. Pawlowsky
|
|
Type de document :
|
article/chapitre/communication
|
|
Année de publication :
|
1997
|
|
Format :
|
p. 3799-3806
|
|
Langues:
|
= Anglais
|
|
Catégories :
|
CHIMIE
|
|
Mots-clés:
|
RHEOLOGIE
;
PRODUIT ALIMENTAIRE
;
FLOCULATION
;
PROTEINE
|
|
Résumé :
|
The influence of iota-carrageenan on the surface activity of bovine serum albumin (BSA) and on the properties of BSA-stabilized oil-in-water emulsions is reported. Surface tension data at low ionic strength indicate a weak electrostatic protein-polysaccharide interaction at neutral pH, which becomes much stronger at pH 6 but disappears in 0.1 M NaCl. The effect of the attractive BSA-iota-carrageenan interaction on the droplet-size distribution and creaming stability of protein-stabilized emulsions (20 vol % n-tetradecane, 1.7 wt % BSA, 5 mM) has been investigated over a range of pH values. At pH 6 the system behavior is interpreted in terms of bridging flocculation leading to a gel-like emulsion network over a certain limited polysaccharide concentration range. This was confirmed by small-deformation oscillatory rheological measurements on equivalent concentrated emulsions (40 vol %). There is a good correlation with the rheology of the dextran sulfate plus BSA emulsions studied previously, suggesting that the flocculation mechanism is similar for the two sets of systems.
|
|
Source :
|
Journal of Agricultural and Food Chemistry, vol.45
|
