Influence of feeding conditions on slowing of gastric emptying by edible gums

The feeding of 4% guar or xanthan gum versus 4% cellulose in a final test meal was expected to slow the gastric emptying of accompanying nutrients, and the degree of this slowing was examined in rats trained to three feeding regimens. Gastric emptying of nutrient energy was calculated from the measured disappearance of fat and of either carbohydrate or total diet residue from the stomach. In experiment 1, rats were ad libitum fed a diet containing 4% cellulose for 6 1/2 days and, after 12 to 14 hours without food, were given a test meal containing either 4% guar or 4% cellulose. In experiment 2, a growth-restricting amount of 6% and 2% guar diets was fed as a single meal on each of 7 days, and the same diets were used for the final test meals. In experiment 3, rats ate 2-hour meals containing 4% and 0% guar gum, or 4% and 0% xanthan gum, on alternate days, and again the same diets were used for the test meal. The feeding of both xanthan and guar gums in a dry form did slow gastric emptying of nutrient energy, although the feeding of 6% versus 2% guar gum was without demonstrable effect (experiment 2). The slowing effect varied with past feeding conditions, being greater in experiment 1 than in experiment 3.