Hydration of casein micelles: kinetics and isotherms of water sorption of micellar casein isolated from fresh and heat-treated milk.
Water vapour sorption isotherms of casein micelles prepared from raw milk and various heat-treated milks were determined. The equilibrium water contents of the heated preparations were markedly lower than that of the raw-milk casein over the whole range of vapour pressures studied. An analysis of the sorption isotherms in the relative vapour pressure range 0.1--0.45, according to the Brunauer, Emmett & Teller (1938) equation, showed that there were significant differences between preparations in the computed monolayer contents. Differences in the rates of water sorption were also observed between the different preparations. As judged from the amount of absorbed water, the influence of the heating methods could be ranked in the order: HTST (92 degrees C) approximately UHT (direct) less than UHT (indirect) less than HTST (72 degrees C).
D000818:Animals; D002364:Caseins; D002417:Cattle; D005260:Female; D005511:Food Handling; D006358:Hot Temperature; D007700:Kinetics; D008823:Micelles; D008892:Milk / Q000032:analysis; D011312:Pressure; D014867:Water
D002364:Caseins; D008823:Micelles; D014867:Water