Time- and temperature-dependent changes in the adsorbed layer on caseinate-stabilized emulsion droplets

• Published in: Food research international 2001, Vol.34 (5), p.369-376
• Main Authors: Euston, S.R., Mayhill, P.G.
• Format: Article
• Language: English
• Subjects: Animal, plant, fungal and microbial proteins, edible seaweeds and food yeasts; Biological and medical sciences; Casein polymers; Emulsion; Food industries; Fundamental and applied biological sciences. Psychology; General aspects; Methods of analysis, processing and quality control, regulation, standards; Sodium caseinate; Storage stability; Surface coverage
• ISSN: 0963-9969; 1873-7145
• DOI: 10.1016/S0963-9969(00)00176-9

Changes in composition of the adsorbed layer in sodium caseinate emulsions stored at different temperatures have been observed. These changes are, in part, dependent on the oil droplet phase (milk-fat or soybean oil). At storage temperatures below 15°C the milk-fat emulsion adsorbed layer exhibits a decrease in surface coverage as a result of casein molecule desorption. This was not observed for soybean oil emulsions. Above 15°C storage temperatures there is a time-dependent and temperature-dependent polymerization of casein molecules in both milk-fat and soybean oil emulsion droplet adsorbed layers. At temperatures below 15°C these changes are explained in terms of the different solid-fat contents of milk-fat and soybean oil. Above 15°C it is hypothesized that chemical changes in the adsorbed layer are taking place.