title: Characterization of high-milk-protein powders upon rehydration under various salt concentrations.
abstract: Rehydration of native micellar casein and native whey isolate protein powders was followed in different ionic environments. Solutions of NaCl and CaCl2 in the concentration range of 0 to 12% (wt%) were used as rehydration media. The rehydration profiles obtained were interpreted in terms of wetting, swelling, and dispersion stages by using a turbidity method. Two behaviors were observed depending on the salt concentration. For native micellar casein powder, a significant change was observed between 3 and 6% NaCl and between 0.75 and 1.5% CaCl2. The first behavior (low salt concentration) presents a typical rehydration profile: quick wetting, swelling, and long dispersion stage. The dispersion stage of the second behavior (high salt concentration) was significantly shortened, indicating a strong modification of the protein backbone. The rehydration of whey protein powder was less influenced by salts. At low salt concentrations, a typical profile for whey powders was observed: wetting with lump formation and no swelling followed by a quick dispersion. At high CaCl2 concentrations, no turbidity stabilization was observed, indicating a possible protein unfolding and denaturation. Additionally, the changes in secondary structures of the 2 proteins upon salt increase were followed by Fourier transform infrared spectroscopy and confirmed the different profiles observed.
authors.affiliation: LIBio, Nancy Université, Laboratoire d'Ingénierie des Biomolécules, 54505 Vandoeuvre Les Nancy Cedex, France.
authors.forename: R
authors.initials: R
authors.lastname: Hussain
authors.forename: C
authors.initials: C
authors.lastname: Gaiani
authors.forename: L
authors.initials: L
authors.lastname: Aberkane
authors.forename: J
authors.initials: J
authors.lastname: Scher
mesh_terms: D000818:Animals; D002122:Calcium Chloride; D003612:Dairying / Q000379:methods / Q000592:standards*; D005511:Food Handling / Q000379:methods*; D008894:Milk Proteins / Q000737:chemistry*; D011208:Powders; D012965:Sodium Chloride; D012996:Solutions; D014867:Water; D000067816:Whey Proteins
chemical_list: D008894:Milk Proteins; D011208:Powders; D012996:Solutions; D000067816:Whey Proteins; D014867:Water; D012965:Sodium Chloride; D002122:Calcium Chloride