Evaluation of diacetyl encapsulated alginate-whey protein microspheres release kinetics and mechanism at simulated mouth conditions

In this paper, diacetyl encapsulated alginate-whey protein concentrate (AL-WPC) microcapsule were prepared based on the emulsification/internal gelation method; and diacetyl release was investigated at the simulated mouth condition in different ratios of artificial saliva (0, 1:4 and 1:8) and three various oral shear rates (0, 50 and 100 s-1). The gotten diacetyl release data were fitted to first-order, Korsmeyer-Peppas, Kopcha, and Makoid-Banakar models to evaluate release mechanisms and kinetics. We showed that the shear rate of release media had a significant (p < 0.05) effect on the release of diacetyl from AL-WPC microspheres, but the saliva ratio had no any significant effect. The diacetyl release data fit well to the all kinetic expression with R2 values greater than 0.93. It was found that the release kinetics of diacetyl from AL-WPC microspheres followed a classical Fickian diffusion.