Microencapsulation of lipid materials by spray drying and properties of products

Lipophilic bioactive materials, such as carotenoids, exhibit various health benefits. To enhance their stability and application in food and pharmaceutical industries, feasibility of microencapsulating these bioactive materials by spray drying was investigated. High‐ and low‐energy emulsification methods were compared at various emulsion compositions and their effects on emulsion stability were characterized. High‐energy method was preferred for safety concerns, as it was able to produce fine emulsions (dₐᵥg < 400 nm) at relatively low surfactant‐to‐oil ratio. The formed infeed emulsions, with MCT oil as core material, gelatin as wall material and primary emulsifier and Tween 80 as secondary emulsifier, were then spray dried using a lab scale spray dryer (Büchi B‐290). Operating conditions were optimized and results demonstrated that spray drying technology could be applied to transform stable infeed emulsions (containing bioactive materials) into microcapsules with desired properties (e.g., low moisture content (5.5–7% (d.b.)), relatively narrow size distribution (d₅₀ between 9.8 and 10.8 μm), and high encapsulation efficiency (around 90%)). So, it is feasible to use this emulsion‐based system to microencapsulate bioactive materials by spray drying. PRACTICAL APPLICATION: Lipophilic bioactive elements are highly susceptible to adverse environment conditions. To overcome these problems, feasibility of microencapsulating these bioactive materials by spray drying was investigated in the present study. A high‐energy method was compared with a low‐energy method in order to find an appropriate emulsification method. The formed infeed emulsion was then spray dried to determine optimum operating conditions. This research should be useful for identifying the most appropriate operating conditions for lipophilic bioactive materials microencapsulation for industrial application especially in food and pharmaceutical industries. Meanwhile, it also provides a possible reference for other scientists and researchers.