In-vitro evaluation of hydrocolloid–based encapsulated fish oil

The release behaviour of hydrocolloid-based encapsulated fish oil was carried out to understand its applicability as a controlled release delivery system. A casein-based Maillard reaction product (MRP), [caseinate–glucose-dried glucose syrup, MRP] and its corresponding non-MRP-based encapsulant materials were used to form stable emulsions with fish oil. The emulsion particle size distribution was found to be uniform with 90% of the particles below 1.3 μm. These oil/water emulsions were spray dried to obtain free-flowing fish oil microcapsules. All casein-based microcapsules had a free fat content of <1% and the encapsulation efficiencies were all >97%. A sequential in-vitro release protocol and a method for evaluation of the released oil in simulated gastric and intestinal fluids (SGF/SIF) were developed and tested in this study. A comparative analysis of release behaviour between caseinate and whey protein-based MRP and non-MRP-based encapsulant materials was also obtained. The amount of released oil after subjecting to the sequential in-vitro protocol was found to be <2% and 36% for caseinate and whey protein-based MRP microcapsules respectively.