COMPARISONS OF VISCOUS PROPERTIES OF OAT AND GUAR GUM AND THE EFFECTS OF THESE AND OAT BRAN ON GLYCEMIC INDEX

Healthy subjects consumed D-glucose (glucose) alone or in the presence of oat gum prepared in a pilot plant (PPOG) or commercial guar gum (GG). Both gums significantly and similarly decreased the postprandial glucose rise as indicated by the glycemic index (GI). The effect of PPOG in a normal meal situation was studied by addition to cream of wheat (CW) to mimic oat bran (OB) porridge. Again, PPOG significantly lowered the postprandial glucose rise. Relative to CW alone, the GI of OB (62%) was similar to that of PPOG plus CW (60%). PPOG was less viscous than both GG and a laboratory-prepared sample of oat gum (LPOG). However, apparent viscosity differences between the gums decreased with increasing shear rate and concentration. LPOG was more pseudoplastic than GG, which in turn was more pseudoplastic than PPOG. At the concentration used in the acute meal tests, PPOG and GG reduced the rate of dialysis of glucose to a similar extent. © 1990, American Chemical Society. All rights reserved.