Thorough characterization and stability of HP-beta-cyclodextrin thymol inclusion complexes prepared by microwave technology: A required approach to a successful application in food

Abstract

BACKGROUND The aim of the present study was to obtain a stable dry powder formulation of cyclodextrins (CDs) encapsulating thymol, for a successful application as an ingredient at industrial scale, as well as, to characterize the thymol-CDs complexes by different techniques. RESULTS Thymol was successfully solubilized in aqueous solutions and the Kc value increased with the pH of the media until neutral pH, obtaining the highest values (2583 ± 176 L mol-1) for HP-β-cyclodextrins (HP-β-CDs). The best encapsulation efficiency of thymol in solid complexes was obtained using the microwave (MWI) encapsulation method. The different characterization techniques have demonstrated the affinity of HP-β-CDs to thymol molecules, forming stable complexes.

CONCLUSIONS The results obtained support the use of the MWI method in the preparation of solid HP- β-CD-thymol complexes, due to the greater encapsulation efficiency and technological and economic advantages for industrial applications.