Maria Stewart

High Amylose White Rice Reduces Post-Prandial Glycemic Response but Not Appetite in Humans

The present study compared the effects of three rice cultivars on postprandial glycemic control and appetite. A single-blind, randomized, crossover clinical trial was performed with 18 healthy subjects, nine males and nine females. Three treatments were administered at three separate study visits: commercially available conventional white rice (short grain), specialty high amylose white rice 1 (Dixiebelle), and specialty high amylose white rice 2 (Rondo). Postprandial capillary blood glucose, venous blood glucose and insulin measurements, and appetite visual analog scale (VAS) surveys were done over the course of two hours. The capillary blood glucose concentrations were significantly lower for Rondo compared to short grain rice at 30 min, and for Dixiebelle and Rondo compared to short grain rice at 45, 60, and 120 min. Capillary blood glucose area under the curve (AUC) was significantly lower for Dixiebelle and Rondo compared to short grain rice. Subjects were significantly more hungry at 30 min after Dixiebelle intake than Rondo intake, but there were no other significant effects in appetite ratings. The present study determined that intake of high amylose rice with resistant starch (RS) can attenuate postprandial blood glucose and insulin response in comparison to short grain rice.

A High Fiber Cookie Made with Resistant Starch Type 4 Reduces Post-Prandial Glucose and Insulin Responses in Healthy Adults

Distarch phosphate is a resistant starch type 4 (RS4) containing phosphodiester cross-links within and between starch molecules. This study examined the glycemic effects of VERSAFIBE 1490™ resistant starch, a distarch phosphate derived from potato, containing 90% total dietary fiber (TDF, AOAC 991.43 method). In this double-blind, randomized, placebo-controlled, cross-over study, 28 healthy adults consumed a cookie containing 24 g fiber from distarch phosphate (fiber cookie) or a control cookie containing 0.5 g fiber that was matched for fat, protein, and total carbohydrate content. Intravenous blood glucose, intravenous blood insulin, and capillary glucose were measured for two hours after cookie consumption. The fiber cookie reduced the post-prandial blood glucose incremental area under the curve from 0 to 120 minutes (iAUC0-120min) by 44% (p = 0.004) and reduced the maximum glucose concentration (Cmax0-120min) by 8% (p = 0.001) versus the control cookie. Consumption of the fiber cookie resulted in a significant 46% reduction of the post-prandial serum insulin iAUC0-120min (p < 0.001) and a 23% reduction in Cmax0-120min (p = 0.007) versus the control cookie. This study shows that distarch phosphate RS4 can be incorporated into a cookie and significantly reduce post-prandial glucose and insulin responses in healthy adults.

Fermentability of Novel Type-4 Resistant Starches in In Vitro System

Resistant starches are non-digestible starches that are fermented in the colon by microbiota. These carbohydrates are prebiotic and can be beneficial to consumer health. Many types of resistant starch exist with varying physical properties that may result in differences in fermentability. The objective of this research project was to compare potential prebiotic effects and fermentability of four novel resistant starches using an in vitro fermentation system and measuring changes in total gas production, pH, and formation of SCFAs (short chain fatty acids). Fecal donations were collected from seven healthy volunteers. Four novel resistant starches, modified potato starch (MPS), modified tapioca starch (MTS), and modified maize starches (MMS-1 and MMS-2), were analyzed and compared to polydextrose and short chain fructooligosaccharides (FOS) as controls. After twenty-four hours of fermentation, MPS and MTS responded similarly in gas production (74 mL; 70.6 mL respectively), pH (5.93; 5.93 respectively), and SCFA production (Acetate: 115; 124, Propionate: 21; 26, Butyrate: 29; 31 μmol/mL respectively). While MMS-1 had similar gas production and individual SCFA production, the pH was significantly higher (6.06). The fermentation of MMS-2 produced the least amount of gas (22 mL), with a higher pH (6.34), and lower acetate production (78.4 μmol/mL). All analyzed compounds were fermentable and promoted the formation of beneficial SCFAs.

Type-4 Resistant Starch in Substitution for Available Carbohydrate Reduces Postprandial Glycemic Response and Hunger in Acute, Randomized, Double-Blind, Controlled Study

Resistant starch (RS) is a type of dietary fiber that has been acknowledged for multiple physiological benefits. Resistant starch type 4 (RS4) is a subcategory of RS that has been more intensively studied as new types of RS4 emerge in the food supply. The primary aim of this randomized, double-blind, controlled study was to characterize the postprandial glucose response in healthy adults after consuming a high fiber scone containing a novel RS4 or a low fiber control scone without RS4. Secondary aims included assessment of postprandial insulin response, postprandial satiety, and gastrointestinal tolerance. The fiber scone significantly reduced postprandial glucose and insulin incremental areas under the curves (43–45% reduction, 35–40% reduction, respectively) and postprandial glucose and insulin maximum concentrations (8–10% and 22% reduction, respectively). The fiber scone significantly reduced hunger and desire to eat during the 180 min following consumption and yielded no gastrointestinal side effects compared with the control scone. The results from this study demonstrate that a ready-to-eat baked-good, such as a scone, can be formulated with RS4 replacing refined wheat flour to yield statistically significant and clinically meaningful reductions in blood glucose and insulin excursions. This is the first study to report increased satiety after short-term RS4 intake, which warrants further investigation in long-term feeding studies.

Gastrointestinal Tolerance and Glycemic Response of Isomaltooligosaccharides in Healthy Adults

Ingredients delivering functional and nutritional benefits are of interest to food manufacturers. Isomaltooligosaccharides (IMOs) which serve as alternate sweeteners fit into this category. IMOs are a mixture of α-(1 → 6) and α-(1 → 4)-linked glucose oligomers, synthesized by an enzymatic reaction from starch (corn, tapioca). The aim of this study was to evaluate the fermentability and glycemic response of IMO in a healthy population. Two randomized, double-blind, placebo-controlled, cross-over human studies were conducted. In the first study (n = 26), participants’ breath hydrogen over 24 h, gastrointestinal tolerance, and glycemic and insulinemic response to BIOLIGOTM IL5040 isomaltooligosaccharide were measured. In another study (n = 10), participants’ two-hour post-prandial glycemic response to BIOLIGOTM IL5040 isomaltooligosaccharide and BIOLIGOTM IL7010 isomaltooligosaccharide was measured compared to dextrose (control). The IMOs differed in the composition of mono and di-saccharide sugars. IMO syrup dose was matched for 50 g of total carbohydrates and was consumed by mixing in water (237 mL/8 oz.). Mean composite gastrointestinal score was not significantly different (p = 0.322) between the control (1.42) and IMO (1.38). Lack of difference in glycemic response (p = 0.662), with no impact on breath hydrogen (24 h; p = 0.319) and intestinal tolerance, demonstrates that IMO is digestible and can be used to replace sugars in product formulations.

Slowly Digestible Carbohydrate for Balanced Energy: In Vitro and In Vivo Evidence

There is growing interest among consumers in foods for sustained energy management, and an increasing number of ingredients are emerging to address this demand. The SUSTRA™ 2434 slowly digestible carbohydrate is a blend of tapioca flour and corn starch, with the potential to provide balanced energy after a meal. The aim of the study was to characterize this starch’s digestion profile in vitro (modified Englyst assay) and in vivo (intact and cecectomized rooster study), and to determine its effects on available energy, by measuring post-prandial glycemia in healthy adults (n = 14), in a randomized, double-blind, placebo-controlled, cross-over study, with two food forms: cold-pressed bar and pudding. The in vitro starch digestion yielded a high slowly digestible fraction (51%) compared to maltodextrin (9%). In the rooster digestibility model, the starch was highly digestible (94%). Consumption of slowly digestible starch (SDS), in an instant pudding or bar, yielded a significantly lower glycemic index compared to a control. At individual time points, the SDS bar and pudding yielded blood glucose levels with significantly lower values at 30–60 min and significantly higher values at 120–240 min, demonstrating a balanced energy release. This is the first study to comprehensively characterize the physiological responses to slowly digestible starch (tapioca and corn blend) in in vitro and in vivo studies.