Alissandratos, ApostolosBaudendistel, NinaFlitsch, Sabine LHauer, BernhardHalling, Peter J2016-01-202016-01-201472-6750http://hdl.handle.net/1885/95528BACKGROUND Natural polysaccharides such as starch are becoming increasingly interesting as renewable starting materials for the synthesis of biodegradable polymers using chemical or enzymatic methods. Given the complexity of polysaccharides, the analysis of reaction products is challenging. RESULTS Esterification of starch with fatty acids has traditionally been monitored by saponification and back-titration, but in our experience this method is unreliable. Here we report a novel GC-based method for the fast and reliable quantitative determination of esterification. The method was used to monitor the enzymatic esterification of different starches with decanoic acid, using lipase from Thermomyces lanuginosus. The reaction showed a pronounced optimal water content of 1.25 mL per g starch, where a degree of substitution (DS) of 0.018 was obtained. Incomplete gelatinization probably accounts for lower conversion with less water. CONCLUSIONS Lipase-catalysed esterification of starch is feasible in aqueous gel systems, but attention to analytical methods is important to obtain correct DS values.The authors thank BASF-The Chemical Company (Germany), for the funding of this project.© Alissandratos et al. 2010 This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://​creativecommons.​org/​licenses/​by/​2.​0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.acylationascomycotachromatography, gasesterificationlipasemagnetic resonance imagingstarch2010-11-2910.1186/1472-6750-10-822016-02-24