Interfacial Tensions of Commercial Vegetable Oils with Water

Abstract

ABSTRACT The pendant drop method, the current method of choice for interfacial tension measurement, was used to obtain the interfacial tensions of a number of vegetable oils with water. Contrary to the reports of earlier workers, all triglycerides examined had similar interfacial tensions with water, all values being in the range 23‐26 mNm −1 . Long chain fatty acids, principal contaminants of commercial oils, had little effect on the interfacial tension. When the oils were exposed to alkaline conditions, the mono‐ and diglycerides formed by hydrolysis caused the interfacial tension to drop rapidly, in agreement with previously reported results for the effect of mono‐ and diglycerides on interfacial tensions.