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

Background: The aims of the present study were to obtain a stable dry powder formulation of cyclodextrins (CDs) encapsulating thymol, for successful use as an ingredient on an industrial scale, and to characterize the thymol-CDs complexes using different techniques.

Results: Thymol was successfully solubilized in aqueous solutions and the Kc value increased with the pH of the media until the pH was neutral, giving 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 for thymol molecules, forming stable complexes.

Conclusions: The results support the use of the MWI method in the preparation of solid HP-β-CD-thymol complexes, due to greater encapsulation efficiency and technological and economic advantages for industrial applications. © 2018 Society of Chemical Industry.