Insulin and glycemic responses in healthy humans to native starches processed in different ways: correlation with in vitro alpha-amylase hydrolysis

Abstract

The aim of the study was to elucidate how extracted starches submitted to food processing (or not) can influence plasma insulin and glucose responses in healthy subjects. Native starches from wheat, manihot, smooth peas, or mung beans were tested either raw, as starch gels (boiled and cooled), or cooked and cooled after a preliminary industrial processing: extrusion cooking for wheat, tapioca for manihot, and noodles for mung beans. Eighteen healthy subjects randomly assigned received three different starches under one form of conditioning. All products were submitted to in vitro alpha-amylolysis. Raw manihot starch produced the lowest (p less than 0.05) metabolic responses. Cooking significantly (p less than 0.01) increased plasma responses. However, cooked mung bean noodles gave metabolic responses similar to those of raw products. Close correlations were found between percentages of in vitro starch hydrolysis at 30 min and mean areas under the glycemic curves and the insulinemic curves (r = 0.95, p less than 0.001).

Relationship between ?-amylase degradation and the structure and physicochemical properties of legume starches

“…Sticky rice, with a lower amylose content, was hydrolyzed very rapidly in vitro, producing a hydrolysis graph similar to that with white bread (Granfeldt et al, 1992). Also, the metabolic responses and in vitro rate of starch hydrolysis of gels made from wheat, manihot, and smooth pea starch were inversely related to the amylose content (17-35%) (Bomet et al, 1989).…”

Rapid carbohydrate digestion rate produced lesser short-term satiety in obese preschool children

“…Several authors have shown that food carbohydrates differ in their in vitro digestion rates (Björck & Siljestrom, 1987. Furthermore, some biological biomarkers such as glycemic and insulinemic levels are dependent on the sensibility of food carbohydrates to enzymatic digestion in the intestinal tract (Bornet et al, 1989;Englyst et al, 1999;Araya et al 2002) and a relationship between the in vitro and biological essays has been reported. Some works have demonstrated in adults and obese adolescents an inverse relationship between glycemic index and satiety (Ludwig et al, 1999;Ludwig 2000;Augustin et al, 2002), but in other's investigations the results showed the inverse tendency (Holt et al, 1996;Raben et al, 1996).…”

Physicochemical Properties of Low-Amylose Yam (Dioscorea Spp.) Starches and its Impact on α- Amylase Degradation in Vitro

“…Studies have also shown that the differences in amylose content may illicit variations in functional characteristics such as digestibility, crystallinity, physical properties, functionality and glycemic indices [7,[13][14]. Such variations can impact on the resulting metabolic effects and susceptibility of the native starch to α-amylase digestion [15,16]. Starch digestibility is of primary significance to health conscious, diabetic and hyperlipidemic individuals as starches that are highly degraded tend to illicit higher insulin demand than those that are less digestible [16].…”

“…Such variations can impact on the resulting metabolic effects and susceptibility of the native starch to α-amylase digestion [15,16]. Starch digestibility is of primary significance to health conscious, diabetic and hyperlipidemic individuals as starches that are highly degraded tend to illicit higher insulin demand than those that are less digestible [16]. Jenkins et al [17] reported that easily digested starches have a higher insulin demand than the slower degrading starches.…”