Annealing induced gelation of xanthan/water systems

摘要: Abstract The effect of annealing at a temperature higher than the gel-sol transition on junction formation in gelation process xanthan/water solutions was investigated by falling ball method (FBM) and differential scanning calorimetry (d.s.c.). Aqueous xanthan dissolved room were inhomogeneous. Although gel-like formed after subsequent cooling, could not be categorised as gel. In contrast, when annealed 40°C, firm gels cooling. (Tg-s) clearly observed FBM. It found that Tg-s gradually increased from 27°C with increasing time approached constant value, i.e. 33°C for 1 wt% sample 40°C 2 sample. time, where levelled off, depended concentration temperature. During 0 to 12 h, it amount non-freezing water estimated d.s.c. fluctuated, although steady increase This phenomenon is interpreted homogenisation solution, molecules become free their molecular assembly through desorption annealing. above results indicate form gel state they are fully sol state.