Study on the preparation of garlic oil microcapsules with regenerated silk fibroin and gelatin as wall material

The garlic oil microcapsules were prepared using regenerated silk fibroin and gelatin as wall materials by spray drying method.The effects of different wall materials, core/wall material ratio and the hydrophilic lipophilic balance ( HLB) values of emulsifier on microcapsule formation with regard to emulsification ability, stability of the emulsifying liquid and microscopic morphology, the embedding rate and the yield of the microcapsule as the index, were discussed in this paper.Results show that regenerated silk fibroin and gelatin are compounded with 1 ∶ 1 ( g/g) into wall solution, and the quality of garlic oil added to the solution accounted for 50% of the wall material.At the same time, the compound emulsifier is added with HLB value of 12.9, the prepared emulsion is stable to ensure that phase separation does not occur before spray drying. The embedding rate and the yield of the microcapsules prepared by spray drying is the largest, which are respectively 85% and88%.Garlic oil microcapsules are 10 ~ 20 μm homogeneous particles and capsule wall surface smooth. The garlic oil retention rate was 88.2% when the microcapsules were stored until 21 d. Therefore regenerated silk fibroin is a kind of ideal garlic oil microcapsule wall material with good protective effect of garlic oil.