Abstract: | Chemical analysis of commercial oat brans (n=10) collected from five different countries showed wide variations in the contents of starch (40–61%), crude protein (9·6–21%), crude fat (8·2–12%), ash (2·0–4·1%), dietary fibre (10·7–19·4%) and mixed-linkage β-glucan (4·7–8·3%). A significant correlation (r=0·83; P<0·005) between the contents of total and extractable mixed-linkage β-glucan was found. Reproducible increases in viscosity were noted for all samples when the finely ground samples were dispersed in phosphate buffer and viscosity development was followed for 100 min. Addition of mixed-linkage β-glucanase greatly reduced the viscosity. Addition of amyloglucosidase, with no detectable mixed-linkage β-glucanase activity, increased viscosity, which could be related to an increased solubilisation of mixed-linkage β-glucan. Highly significant correlations (r>0·90) were found between the contents of both total and extractable mixed-linkage β-glucan and viscosity after dispersion. © 1998 SCI. |