Determination of average molecular weight of guar gum by a simple twice headspace extraction gas chromatographic technique

This paper proposed a new method for the determination of the viscosity average molar mass of guar gum, based on a volatile tracer assisted twice headspace extraction gas chromatographic technique. The feasibility study showed that n-butanol was a suitable tracer to be used in this method. The results showed that the present method had a good precision (with the relative standard deviation < 0.86%) and good accuracy (in which the relative differences were within 7.94% when compared with the reference method). The present method is simple and practical. It can conduct an automated measurement when a batch sample testing is required.