Lipid type and location of the relative humidity gradient influence on the barrier properties of lipids to water vapor

Abstract

Large differences exist in the water vapor (WV) permeance of films made from different lipids (stearic acid [SA], tristearin [TS], stearyl alcohol [StA], hexatriacontane [HT], beeswax [BW], and acetylated monoglycerides [AG]). Differences in hydrophilic groups in the various lipids tested account for much of these differences. It is also interesting that the WV permeance of films made from BW or BW and AG increased as the relative humidity (RH) gradient was decreased by raising the dry-side RH from 0% to 65 or 80% (wet-side RH always 100%). This behavior is important because edible films intended as barriers to WV transmission will often be exposed to the latter conditions.