encapsulation of alpha-tocopherol using polycaprolactone and tween 20: formulation and a perspective for scaling up using micro-channel

Alpha-tocopherol or vitamin e is well known for its beneficial properties for human health. this bioactive compound can be recovered from various agricultural resources through extraction and separation processes. in order to prolong its shelf-life and maintain its bioavailability, the purified substance can be further encapsulated using a biocompatible reagent. in this work, the encapsulation factors including the concentration of polycaprolactone (pcl), concentration of tween 20, and the ratio of the organic phase to the aqueous phase were experimentally investigated. the box–behnken experimental design was employed to determine the optimal encapsulation condition in a small batch system. the results revealed that, at the adjusted optimal condition, 98.43% encapsulation was achieved using the concentrations of pcl of 6 g/l, concentration of tween 20 of 0.5 g/l, and the ratio of organic phase to aqueous phase of 1:2. based on the optimal condition of the batch process, the continuous micro-channel encapsulator was employed for continuous encapsulation with different residence times. for the residence time of 1 s, this system provided an encapsulation efficiency of 92.48% with outstanding productivity of 73.99 mg/ml×min. this work can be further developed to increase the production capacity via parallel processing of micro-channels.