INFLUENCE OF EXTRACTION METHODS ON THE COMPOSITION OF VARIOUS FATTY ACIDS IN SHEA BUTTER PROCESSED FROM SELECTED SHEA KERNELS

Abstract

The functional groups and the constituent composition of Shea butter (a mixture of stearic, oleic, linoleic, palmitic and arachidic fatty acids along with bioactive components) are greatly influenced by the climatic conditions of the Shea tree, the processing conditions of the Shea kernel, and the extraction methods of Shea butter. Also, the choice and application of Shea butter (Pharmaceuticals, Cosmetics, Chocolates) are greatly influenced by the composition and functional groups present in butter. In this research, optimally processed Shea kernel (4.3-day Shea fruit picking period, 120 minutes Shea nut boiling duration, 86 oC drying temperature) and locally processed Shea kernel were subjected to a potpourri of Shea butter extraction methods to investigate their influence on the variations of the constituent fatty acids. Fourier Transformation infrared spectroscopy (FTIR) and Gas Chromatography-Mass Spectroscopy (GC-MS) techniques were used to establish the functional groups and the mass composition of the constituent fatty acids. The results show that for all samples, stearic and oleic acids predominate jointly, constituting a minimum of 84%. Also, samples contained alkane, alkene, carbonyl, and ester functional groups. Shea butter obtained from optimally processed Shea kernel and optimum traditional extraction method gave 45.9% and 39.2% mass composition of Stearic and Oleic acid, respectively, and traces of the other acids and the balance bio-actives. Results for other Shea kernel treatment and butter extraction methods are also reported.