Amylose forms complexes with fatty acids under certain conditions. These complexes could be potentially used as delivery systems of essential fatty acids in the human organism. This work uses dynamic interfacial tension measurements as means for investigating such complexes for the first time in the literature. The Whilelmy plate technique and the pendant drop / axisymmetric drop shape analysis method were used for the measurement of equilibrium and dynamic interfacial tension. First the interfacial tension at the water/air interface was measured for three fatty acids (capric, myristic and oleic) in 0.1 N KOH solution at three different concentrations (6*10-2, 6*10-3 and 6*10-4 g/100ml). The surface tension of amylose in 0.1 KOH solution was measured as well. Then amylose and fatty acid solutions were mixed to fatty acid-to-amylose weight ratios of 10, 1 and 0.1 % and a fatty acid concentration in the final solution equal to the fatty acid solutions without amylose. For all examined systems the dynamic interfacial tension of the mixed amylose – fatty acid solution was significantly higher than this of the fatty acid solution, showing that some of the fatty acid was no longer available to adsorb at the interface and suggesting its inclusion in the complex. Besides, the dynamic interfacial tension of the mixed system was lower compared to the amylose solution indicating that some of the fatty acid did not participate in the complexes and that the fatty acid excess depended on fatty acid-to-amylose ratio.
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