The present study focused on using the millifluidic-inverse gelation platform to produce core-shell millicapsule filled with cinnamon W/O emulsion as an intestinal delivery system. Effects of variables in the designed encapsulation method (flow rates of two phases and alginate concentration) on encapsulation efficiency (EE), loading capacity (LC), size, sphericity factor (SF), and Young modulus were optimized. The best-selected ranges of emulsion Z-average diameter and alginate viscosity were 800–1400 nm, and 16.63–153.61 mPa.s, respectively. According to the Capillary and Weber numbers, the dripping regime was confirmed in the tube during droplet formation. The optimal millicapsule had a 2.50 mm diameter, 0.97 SF, 95.83% EE, 51.39% LC, and 8.5× 104 Pa Young modulus. The smooth surface of the millicapsules and the uniform distribution of the oil and water droplets inside the emulsion dispersed phase were evidenced by SEM and CLSM, respectively. In-vitro digestion demonstrated that millicapsules act as a pH-dependent delivery system to release the oil into the small intestine. Mechanical stability reached a maximum in the gastric phase. High emulsion loading acted as a soft filler, which improved the mechanical stability of millicapsules. Peppas-Sahlin was the best model to describe the release behavior in the mouth, stomach, and small intestine.
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