Hur påverkar lösligt β-glukan GI-värdet? : Analys av vetebaserat bröd

Sammanfattning: The work was done in collaboration with Lantmännen's research foundation to produce a new and health-promoting bread. The dietary fiber beta-glucan was added to bread at a sufficiently high content to have positive health effects on blood cholesterol and blood sugar levels. The bread should also have a high sensory quality. In this project the effects of addition of beta-glucan on the theoretical GI (glycemic index) and GL (glycemic load) were investigated. An in vitro analysis was used, and the GL was calculated from the GI. These analyses were carried out on both freeze-dried bread and fresh bread containing different concentrations of beta-glucan. A sensory analysis was also done to see if there was any difference between the control bread and the bread containing the beta-glucan. The purpose of the work was to investigate how the theoretical GI value and the theoretical GL value are affected by two different preparations of beta-glucan (with concentration of 32% respectively 75% beta-glucan) in bread with end concentrations of 0.2 and 2.0 % beta-glucan of the total quantity of flour. The result indicates that there is significant effect on GI and GL of beta-glucan in wheat-based bread. Between the reference bread and the 0.2% bread of the freeze-dried bread, a significant difference was seen with a p-value of 0.048 in a paired t-test. It also was a significant difference between the reference bread and the 2.0% bread with a pvalue of 0.014 in a paired t-test. The GI values were calculated to 65 and 63 respectively for 0.2 and 2.0% beta glucan for the freeze-dried bread. The GI value for the fresh bread were calculated to 68 and 52 respectively for 0.2 and 2.0% beta glucan. The GL-values for the fresh-bread were calculated to 79 and 60 respectively for 0.2 and 2.0% beta glucan. The GL-values for the freeze-dried bread were calculated to 38 and 37 respectively for 0.2 and 2.0% beta glucan. A significant difference was seen between the reference bread and thefresh bread containing 2% added betaglucan (p-value = 0.002using t-test). The fresh bread with 0.2% added betaglucan had at about the same GI value as the reference bread and a significant difference could not be seen (p = 0.7642). In other studies, whole grain flour and a dietary fiber content of 15-45 g / serving have been shown to have an effect on the GI and GL values. The desired result is to have attenuated effects on blood sugar levels in the blood after food intake and thus be able to achieve prerequisites for blood sugar claims. To achieve the desired effect a whole-wheat flour should be used to raise the dietary fiber content and reduce the proportion of wheat flour and glucose available.