Properties of Sodium Caseinate Film-Forming Dispersions and Films

Abstract

The flow properties of sodium caseinate (NaCAS) film-forming dispersions were studied as a function of protein and glycerol concentration. Apparent viscosity vs. concentration profiles showed a disruption at about 10% (wt/wt) NaCAS. This was interpreted in terms of protein-water and protein-protein interactions. The presence of glycerol in the NaCAS film-forming suspensions reduced the viscosity of aqueous NaCAS as a consequence of decreasing protein-protein and protein-solvent interactions through the hydrogen bonding formation between the glycerol, the polypeptide chain of NaCAS, and water molecules. For higher concentration of glycerol, viscosity of NaCAS dispersions increased as a result of increasing total solid content. The glass transition temperature for solid films of 10% (wt/wt) NaCAS decreased with the glycerol content. The glycerol-protein interactions reduced the protein-protein interaction and, thus, increased the intermolecular spacing, leading to higher protein chain mobility and water vapor permeability.

Steady and dynamic oscillatory shear rheological properties of ketchup–processed cheese mixtures: Effect of temperature and concentration

“…Marchesseau et al (1997) also pointed out that the compactness of the protein microstructure decreased with increasing pH, indicating decreasing protein-protein interactions that caused the decrease in viscosity. Accordingly, Khwaldia et al (2004) explained a decrease in the apparent viscosity of sodium caseinate (NaCAS) film-forming dispersions by decreasing protein-protein interactions through the hydrogen bonding formation between polypeptide chain of NaCAS and water molecules.…”

Effect of a sodium caseinate edible coating on berry cactus fruit (Myrtillocactus geometrizans) phytochemicals

“…The coating suspension was a modification of procedures described by Khwaldia, Banon, Perez, and Desobry (2004) using a mixture of sodium caseinate (Na-Cas) and two different plasticizers, D-sorbitol and glycerol. Fruits were separated into three different groups and sprayed with distilled water (C), sodium caseinate and sorbitol coating suspension (S), and sodium caseinate and glycerol coating suspension (G).…”

Antioxidant properties of polyphenols incorporated in casein/sodium caseinate films

“…Films made with CAS (100%e70%) and NaCAS (0%e30%) were manufactured as described by Khwaldia et al (2004) and Schou et al (2005) with some modifications. Sodium caseinate dispersions at a concentration of 10% (w/w) were obtained by dispersing the appropriate mass of NaCAS powder with stirring in distilled water at 60 C for 30 min.…”

“…Caseinate films are suitable for use as coating material for some food products, such as cheese, vegetables and fruits, because of their transparent, flexible, and bland nature. Furthermore, they are used as microencapsulating agents of flavours and medicines (Khwaldia, Banon, Perez, & Desobry, 2004). Due to the structure and amino acid sequence of casein, it appears that the mechanism of film formation involves hydrogen bonding, electrostatic interactions and hydrophobic forces (McHugh & Krochta, 1994).…”