Enzyme resistant dextrins from potato starch as potential prebiotic

Overweight, obesity, and diabetes are major health threats, which become worldwide epidemics. For intervention of these serious health problems, and to provide healthy food choices to meet consumers' needs, scientists and food industry face a major challenge in producing functional food, containing prebiotics, probiotics, and symbiotics. These products must still be tasty, safe to consume and low in cost. Poland is the largest producer of potatoes in EU, and potato consists at least 13% of starch, which is the major ingredient for food products. Starch-based ingredients include products such as starch syrup, maltodextrins, modified food starch, maltose and dextrose. The lifestyle of modern society demands the use of these ingredients, as they are components of foods, which are easy to prepare, economical, and taste good. However, because these ingredients are rapidly and fully digestible, they can lead to elevated level of blood glucose immediately after ingestion. Therefore, it is necessary to look for new less digestible food ingredients. To meet this demand enzyme-resistant dextrins were prepared by thermolysis of potato starch in the presence of hydrochloric and citric acids in sealed containers at 130 degrees C for 3, 4, and 5 hours. The studies indicated possibility of preparation of well-soluble (up to 82%) dextrins containing about 86% of molecules with weight average molecular weight (M-w) of 4x10(3) g/mol (aver. DP approximate to 25) (DP: degree of polymerisation), and average chain length (CL) of 10.6. The citric acid-modified dextrins contained up to 22% of TDF including low-molecular resistant maltodextrin as determined by AOAC Official Method 2001.03. Dextrin prepared by heating of potato starch with hydrochloric, and citric acids at 130 degrees C for 4 hours showed the best stimulation of probiotic bacteria. That dextrin was less available carbon source for bacteria isolated from gastrointestinal tract of healthy 30-year old human volunteers. In order to confirm prebiotic effect of that dextrin further clinical studies are required.