Release behavior of allyl sulfide from cyclodextrin inclusion complex of allyl sulfide under different storage conditions.

The stability of allyl sulfide, an organosulfur compound present in garlic oil, in its α-, β-, and γ-cyclodextrin inclusion complexes was investigated under various storage conditions. The complexes of cyclodextrins and allyl sulfide were prepared by spray drying. The storage temperature, relative humidity, and initial moisture content of the inclusion complex had different effects on the release rate of allyl sulfide. Allyl sulfide in α-cyclodextrin complexes had a lower release rate than in β- and γ-cyclodextrin complexes at 100 °C and at 50 °C under 6, 40, 54, and 73% relative humidity. The initial moisture content affected only the release rate of allyl sulfide from α-cyclodextrin complexes. The release behavior of allyl sulfide can be correlated with the first-order release rate equation with a normal Gaussian distribution of free energy of activation of release rate constant. The results indicated α-cyclodextrin is a suitable material for controlled release of allyl sulfide.