The encapsulation efficiency was calculated as the ratio between the mass of SF in the final product and its initial mass to be encapsulated. About 500 mg exactly weighed microcapsule sample was dissolved in distilled water to form homogeneous solution. Then SF was extracted two times with equal volumes of dichloromethane, which was combined and dried in a vacuum rotary evaporator. The residue was dissolved by methanol and filtered through a 0.45 μm membrane. The total SF in the solution was determined by HPLC.