Effect of fatty acids on physical, mechanical and moisture barrier properties of salep - based edible film

Salep composite films containing 0±30% (w/w) oleic acid or stearic acid – were prepared through emulsification and their physical, mechanical, and barrier properties were evaluated and compared. Emulsified films were softer than pure films. Addition of the fatty acids to salep films significantly improved the WVP (P<0.05), but lowered the tensile strength. Stearic acid was more effective than oleic acid in reducing the WVP, but films with oleic acid showed better mechanical properties overall than those with stearic acid. Also the presence of fatty acids decreased solubility in water and caused the films to become opaque. On the other, fatty acids showed different effects on the elongation at break. This work showed that when taking all the studied variables into account, films formulated with oleic acid were found most suitable for various food applications.