"Rh\u00E9ologie" . "Text" . "R\u00E9hydratation" . "\u00C9tude des m\u00E9canismes de r\u00E9hydratation des poudres laiti\u00E8res, influence de la structure et de la composition des poudres" . . . "XPS" . . . . "Cas\u00E9ine" . . . "Deux m\u00E9thodes permettant une caract\u00E9risation de la r\u00E9hydratation des poudres de prot\u00E9ines laiti\u00E8res in situ ont \u00E9t\u00E9 d\u00E9velopp\u00E9es et valid\u00E9es. La premi\u00E8re met en jeu un r\u00E9acteur instrument\u00E9 comprenant des sondes de turbidit\u00E9, de pH et de conductivit\u00E9. La seconde utilise un rh\u00E9om\u00E8tre \u00E9quip\u00E9 d'un syst\u00E8me vane adapt\u00E9 \u00E0 l'\u00E9tude des syst\u00E8mes particulaires. Dans une seconde partie, ces m\u00E9thodologies sont coupl\u00E9es \u00E0 d'autres techniques (spectroscopie des photo\u00E9lectrons X, microscopie optique, granulom\u00E9trie...) dans le but de comprendre l'influence de la composition biochimique des poudres sur la r\u00E9hydratation. Ainsi, en fonction du type de prot\u00E9ine r\u00E9hydrat\u00E9e, les propri\u00E9t\u00E9s de r\u00E9hydratation seront totalement oppos\u00E9es. Ces comportements sont attribu\u00E9s \u00E0 la structure des prot\u00E9ines et \u00E0 la localisation des composants (prot\u00E9ine, lipides et lactose) dans la particule. L'influence du proc\u00E9d\u00E9 technologique sur la r\u00E9hydratation a \u00E9galement \u00E9t\u00E9 \u00E9tudi\u00E9e. La granulation, le traitement thermique des prot\u00E9ines et le type de m\u00E9lange (m\u00E9lange \u00E0 sec ou co-s\u00E9chage) vont tous influencer les transferts d'eau en cours de r\u00E9hydratation. Enfin, des modifications importantes des propri\u00E9t\u00E9s de r\u00E9hydratation des poudres au cours de leur conservation ont \u00E9t\u00E9 reli\u00E9es \u00E0 des variations dans la r\u00E9partition des composants au sein de la particule de poudre" . "Prot\u00E9ines solubles" . "Dairy powder rehydration, influence of powder structure and composition" . "Lait en poudre -- Composition chimique" . . "2006" . . . . "Th\u00E8ses et \u00E9crits acad\u00E9miques" . "Two methods allowing the investigation of dairy powders rehydration were developed and validated. The first method involved dispersing powder in a stirred vessel equipped with three sensors (turbidity, pH and conductivity) under standardized conditions. The second one used a Stress Tech Rheometer equipped with a custom built paddle stirrer adapted to particulates systems. In a second part, these methods were coupled with other techniques (X-ray Photoelectron Spectroscopy, microscopy, particle size distribution...) in order to characterize how powder biochemical composition influences on rehydration. Indeed, the rehydration properties were found totally different depending on the rehydrated protein nature. These different behaviours were attributed to the protein structure and to the compound (protein, fat and lactose) localisation in the particle. Some technological effects on powder rehydration were also analysed. The granulation, the protein thermal treatment and the type of mix (dry mixing or co-drying) were found to greatly influence water transfers during rehydration. Finally, a deterioration of the rehydration properties were investigated during powder conservation. The rehydration deterioration was correlated to a modification of compounds repartition in the particle" . . . "\u00C9tude des m\u00E9canismes de r\u00E9hydratation des poudres laiti\u00E8res, influence de la structure et de la composition des poudres" .