Effects of heat on physicochemical properties of whey protein-stabilised emulsions

Coalescence stability of emulsions containing globular milk proteins

“…As known from literature, the protein molecules usually change their conformation after adsorption and/or thermal treatment, and this leads to modifications in the properties of the adsorption layers [34,35,[112][113][114][115][116][117][118]. In the current section, we present experimental results for the effects of storage time and heating on emulsion coalescence stability.…”

“…The protein adsorption also increases in a step-wise manner with the heating temperature: in emulsions heated at T = 78°C, Γ is practically the same as in the non-heated emulsions (2.8 mg/m 2 ), whereas it increases up to 3.8 mg/m 2 after heating at T = 85 and 90°C (similar increase in Γ after heating was reported in Refs. [114,121]). Thus, the increased emulsion stability after heating at T = 85°C is at least partially due to increased steric repulsion between the protein adsorption layers.…”

The use of sedimentation field-flow fractionation in the size characterization of bovine milk fat globules as affected by heat treatment

“…Tangsuphoom and Coupland (2005) suggested that both flocculation and possibly a slight degree of coalescence accounted for the increase in particle size in heated coconut emulsions. Protein stabilized emulsions have been shown to flocculate after heating as the protein-protein associations formed bind the droplets together in a network (Siliwinski, Roubos, Zoet, van Boeckel, & Wouters, 2003). Heat-denatured whey proteins form complexes with casein micelles because of increasing hydrophobicity and at higher temperatures this complex formation is stronger than at lower temperatures (Erdem & Yuksel, 2005).…”

Flocculation of protein-stabilized oil-in-water emulsions

“…Solid-like flocculated emulsion gels may be generated from liquid-like whey protein emulsions by thermal processing [134][135][136] and acidification [137][138][139]. The extent of heat-induced flocculation is dependent on various factors, such as the treatment time/temperature and the unadsorbed protein concentration [140,141]. The flocs are held together by a combination of hydrophobic interactions and covalent disulfide bonds between proteins adsorbed to different droplets [142].…”