Structural and Functional Properties of Caseinate and Whey Protein Isolate as Affected by Temperature and pH

Abstract

The structural properties, i.c., active sulfhydryl (SH), flexibility and hydrophobicity, and functional properties, i.e., solubility,. emulsion activity (EA), emulsion stability (ES), foam overrun (FO) and foam stability (FS), of commercial sodium caseinate (SC) and whey protein isolate (WPI) solutions were investigated.at pH 6, 7 and 8 and at 25, 55 and 65°C. WPI contained a higher concentration of active SH and was more hydrophobic than SC. WPI provided comparable solubility and EA, lower FO, but higher FS than SC. Temperature and pH effects on the two proteins were somewhat inconsistent.

Inulin like lyoprotectant of bovine plasma proteins concentrated by ultrafiltration

“…Some of these properties are solubility, emulsifying capacity and foam capacity. The method of Lee, Morr, and Ha (1992) with several modifications was used to determine the protein solubility at room temperature (22 ± 1) C. 1% (w/v) solution of each lyophilized protein concentrates in 0.01 M phosphate buffer (pH adjusted to between 3 and 9 with either 1 N HCl or 1 N NaOH, respectively) was prepared and stirred for 5 min. Then it was centrifuged in a refrigerated ultracentrifuge (Beckman J2-HS, USA) at 20,000 rpm for 30 min at 5°C.…”

Combined effect of dynamic heat treatment and ionic strength on the properties of whey protein foams – Part II

“…These parameters must be adjusted to produce a level of denaturation suitable for obtaining a satisfactory polymerization degree in order to produce rigidity and cohesion of the interfacial film during foaming, without proteins agglomeration due to an excessive denaturation (Tosi, Canna, Lucero, & Ré, 2007). The literature shows first that the ability of the b-Lg to form foams could be enhanced by denaturation (Lee, Morr, & Ha, 1992). According to Phillips and Kinsella (1990), partial unfolding of the protein molecule and the exposure of hydrophobic groups increases the hydrophobic interactions and enhances foam formation.…”

Micellization of casein‐graft‐dextran copolymer prepared through Maillard reaction

“…[17][18][19][20][21] Between pH 6.5 and 8, sodium caseinate exists as a polydispersed mixture of four casein molecules. 12,13 In the food system, casein has many functions, such as emulsification, water binding, fat binding, and texturization. 22,23 These merits endow casein with the ideal matrix to fabricate nanomaterials to carry both hydrophilic and hydrophobic drugs for advanced drug delivery.…”