Microencapsulating properties of sodium caseinate

Emulsions were prepared with 5% (w/v) solutions of sodium caseinate (Na Gas) and soy oil at oil/protein ratios of 0.25-3.0 by homogenization at 10-50 MPa. Emulsions were spray-dried to yield powders with 20-75% oil (w/w), Emulsion oil droplet size and interfacial protein load were deter-mined. Microencapsulation efficiency (ME), redispersion properties, and structure of the powders were analyzed. The size of emulsion oil droplets decreased with increasing homogenization pressure but was not influenced by oil/protein ratio. Emulsion protein load values were highest at low oil/protein ratios. ME of the dried emulsions was not affected by homogenization pressure but decreased from 89.2 to 18.8% when the oil/protein ratio was increased from 0.25 to 3.0, respectively. Mean particle sizes of reconstituted dried emulsions were greater than those of the original emulsions, particularly at high oil/protein ratios (>1.0), suggesting destabilization of high-oil emulsions during the spray-drying process.