Preparation and characterization of β-cyclodextrin inclusion complexes as a tool of a controlled antimicrobial release in whey protein edible films

Abstract

Control release of eugenol and carvacrol is difficult to obtain even when WPI is used as a carrier. Active compounds cyclodextrin inclusion complexes may encourage molecular interaction intervening in their release. α-, β-, and γ-cyclodextrin (α-, β-, and γ-CD) complexes were prepared and added to WPI edible films. Inclusion/spray-drying process yield was low (<50%, weigh basis). β-CD was selected because it showed a higher retention for eugenol (50.4%, molar basis) and carvacrol (79.6%, molar basis). Protons that lie inside the β-CD cavity and aromatic rings protons from active compounds are involved in host–guest interaction. The initial molar ratio using during complex preparation was not maintained. The final stoichiometric ratio of β-CD:eugenol and β-CD:carvacrol was 1:0.5 and 1:0.7, respectively, showing a β-CD cavity preference for carvacrol. The study suggests that adding β-CD to the WPI matrix resulted in a decreased release rate in a food simulant medium (ethanol: water, 1:1, v/v) when there is an effective interaction between β-CD and active compound. This fact shows significance for delivery of antimicrobial compounds that must release gradually in time.