Four acetostearin products with increasing acetylation degree were synthesized by chemical inter-esterification followed by fractionation/blending stages. Their physical properties and functional barrier properties were studied and compared to the properties of technical tristearin. Increasing acetylation degree (AD) modified the triacylglycerols crystal habits and probably led to an increase in acyl chain fluidity, which induced, at macroscopic levels, a decrease in solid fat content (SFC), in melting point, in surface and bull: material hydrophobicity, and an increased moisture effective diffusivity. Water vapor permeability (WVP) coefficients of the materials were partially influenced by the AD factor, but also by the development of macroscopic cracks in lipids presenting high SF C. Acetylated stearin up to 47% (acetyl mol/mol of esterified chain) presented the lowest WVP at 20 degrees C resulting from an adequate balance between hydrophobicity and mechanical properties of the material.