Ca²⁺‐Induced Gelation of Pre‐heated Whey Protein Isolate

Abstract

Addition of CaClz to pre-heated whey protein isolate (WPI) suspensions caused an increase in turbidity when pre-heating temperatures were 2 64°C. Pre-heating to 2 70°C was required for gelation. WPI suspensions which contained CaCl, became turbid at 45°C and formed thermally induced gels at 66°C. Thermally and Ca*+-induced gels showed significant time/temperature effects but the penetration force values in the Ca*+-induced gels were always lower. However, Ca*+-induced gels were higher in shear stress at fracture. The Ca*+-induced gels had a fine-stranded protein matrix that was more transparent than the thermally induced gels, which showed a particulate microstructure.

Optimization of dynamic loop mixer operating conditions for production of O/W emulsion for cell microencapsulation

“…In such devices, shear, energy dissipation and dynamic pressure are not gras était uniquement dépendante de la vitesse de recirculation dans le mélangeur à boucles (P < 0,05). Une vitesse de rotation de 2500 rpm, correspondant à une population de globules gras avec un D [3,2] (v,0,9) de 49 mm a été sélectionnée pour la production par séchage-atomisation de microcapsules multiphasées possédant un diamètre inférieur à 100 mm, contenant des particules de poudre micronisée de bactéries lyophilisées. Cette recherche a montré que le mélangeur à boucle permet de produire, en continu et avec une productivité élevée, une émulsion huile de beurre/protéines sériques avec un contrôle élevé de la taille des globules de gras et une faible dispersion.…”

“…The process variable levels studied and coded variables are presented in Table I. The BBD was used in the present study to determine the relationships between the fat globule size distribution parameters (D [3,2],…”

“…Particle sizes were converted from individual diameter to the volume of the diameter equivalent sphere and used to calculate the volume size distribution of fat globules. The Sauter mean diameter or volume-surface mean diameter D [3,2], defined as the diameter of the particle with volume to surface area ratio equal to the arithmetic mean of the volume to surface area ratio calculated for all particles in the sample, the 10% volume fractile of the particle size distribution D(v, 0.1), the volume median…”

“…Another important functional characteristic of whey proteins is their ability to form salt-induced gels at room temperature. Cold-set gelation is generally achieved by adding Ca 2+ ions to a WPI suspension preheated under specific conditions [3,15]. The production of water-insoluble wheyprotein beads using an emulsification/cold gelation process has recently been proposed for protection and subsequent release in the intestine of bioactive molecules sensitive to the gastric environment [4].…”

Application Potential of Food Protein Modification

“…Aggregated protein can act as a nucleation prerequisite to induce gelation, albeit at high protein concentration (Alting et al, 2003;Barbut & Foegeding, 1993;Ju & Kilara, 1998). Processing conditions and storage can induce protein aggregation, even at ambient temperatures (Promeyrat et al, 2010;Santé-Lhoutellier et al, 2008).…”