Investigation and modeling of the release kinetics of yarrow (Achillea millefolium L.) essential oil from gelatin-sodium alginate active film into food simulants

In the present research, gelatin-sodium alginate films incorporated with various concentrations of yarrow essential oil were prepared. The release of yarrow essential oil from gelatin-sodium alginate films into watery (distillated water), acidic (acetic acid 3%), alcoholic (ethanol 10%) and fatty (ethanol 85%) food simulants was measured at 25 ºC. In each simulant, all films had similar release profiles with an initial fast release followed by a sustained slow release. Results indicated that yarrow essential oil released faster from film in watery food stimulant due to the swelling in water. Films maintained their structures in fatty food simulant after 240 h. The artificial neural network (ANN) and mathematical (first order, Kopcha, Higuchi, Korsmeyer-Peppas, Weibull function and Hixson-crowell) models were applied to describing essential oil release from film. Mathematical modeling results indicated that Weibull model could satisfactorily describe the release kinetics of essential oil for all food simulant (minimal correlation coefficient (R2) and mean square error (MSE) of 0.991 and 10.22, respectively). The ANN model with 3-17-15-1 topology accurately predicted the kinetic release of yarrow essential oil from gelatin-sodium alginate film in all food simulant with R2 = 0.999 and MSE = 0.56.