Preparation of Starch-Fatty Acid Esters from Agro-Based Raw Materials (Corn Starch, Cassava Starch, Coconut Oil, and Castor Seed Oil)

Abstract

The preparation of starch-fatty acid esters is investigated for corn starch and cassava starch. The fatty acid contents are obtained from the hydrolysis of coconut oil and castor oil respectively and are characterized by GC/MS techniques. The major fatty acid component of coconut oil is found to be lauric acid (34%) while that of castor oil is ricinoleic acid (84%). Four different starch-fatty esters are prepared, namely cassava starch-coconut fatty acid esters (CacoFAE), cassava starch-castor fatty acid ester (CacaFAE), corn starch-coconut fatty acid ester (CocoFAE), and corn starch-castor fatty acid ester (CocaFAE). The starch-fatty acid esters are analyzed using FT-IR and liquid chromatography-mass spectrometer techniques. All the esterified starch-fatty acid esters contain the C=O absorption peak at 1707 cm−1 which is the peak corresponding to the ester group formed between the starch hydroxyl and fatty acid carboxylic functions. The major fatty acid eluted from LC-MS for CacoFAE and CocoFAE is lauric (dodecanoic) acid with 67.4% and 74% respectively while ricinoleic acid (58%) is obtained for CacaFAE. The data for CocaFAE are mainly dominated by the ester of the fatty acids.