Properties of xanthan obtained from agricultural wastes acid hydrolysates

The properties of xanthan produced by Xanthomonas campestris from agricultural wastes acid hydrolysates (AHW-xanthan) and standard xanthan were compared. Both polymers had similar acetyl/pyruvyl ratio but had different amounts of other compounds, and therefore conditioned wide differences in viscosity of solutions. AHW-xanthan was less pseudoplastic and gave solutions of lower apparent viscosity than standard xanthan. In contrast, AHW-xanthan solutions were more stable to changes in temperature, pH and ionic strength than standard xanthan. These results suggest that xanthan obtained from agricultural wastes acid hydrolysates, low-cost and abundant substrates, may found additional applications to standard xanthan because of its higher stability and lower production costs. (C) 2003 Elsevier Ltd. All rights reserved.