Enrichment of pasta with faba bean does not impact glycemic or insulin response but can enhance satiety feeling and digestive comfort when dried at very high temperature

Abstract

Enrichment of durum wheat pasta with legume flour enhances their protein and essential amino acid content, especially lysine content. However, despite its nutritional potential, the addition of a legume alters the rheological properties of pasta. High temperature drying of pasta reduces this negative effect by strengthening its protein network. The aim of our study was to determine if these changes in the pasta structure alter its in vitro carbohydrate digestibility, in vivo glycemic, insulin and satiety responses. We also investigated if high temperature drying of pasta can reduce the well-known digestive discomfort associated with the consumption of legume grains. Fifteen healthy volunteers consumed three test meals: durum wheat pasta dried at a low temperature (control), and pasta enriched with 35% faba bean dried at a low and at a very high temperature. When enriched with 35% legume flour, pasta maintained its nutritionally valuable low glycemic and insulin index, despite its weaker protein network. Drying 35% faba bean pasta at a high temperature strengthened its protein network, and decreased its in vitro carbohydrate digestion with no further decrease in its in vivo glycemic or insulin index. Drying pasta at a very high temperature reduced digestive discomfort and enhanced self-reported satiety, and was not associated with a modification of energy intake in the following meal.

Structural, Culinary, Nutritional and Anti-Nutritional Properties of High Protein, Gluten Free, 100% Legume Pasta

“…F and L presented the lowest RAG (61.8 and 62.5%, respectively) and the highest SAG (36.4 and 36.0%, respectively). RAG values were lower than those reported in the literature for wheat pasta (67±0.7% of available carbohydrates) [17], but close to those reported for 35% faba enriched pasta (64.9±3.2% of available carbohydrates). BG pasta presented a significantly higher RAG and lower SAG than F and L pasta.…”

“…RS was twice higher in all legume pasta than in C pasta. C pasta had a similar RS to RS values reported in the literature for wheat pasta [17]. A range of 0.88 to 1.69 g/100g (w.b) is reported in 35% faba bean and split pea enriched pasta [16, 17].…”

“…C pasta had a similar RS to RS values reported in the literature for wheat pasta [17]. A range of 0.88 to 1.69 g/100g (w.b) is reported in 35% faba bean and split pea enriched pasta [16, 17]. The amount of available carbohydrates was slightly but significantly higher in F (20.5%) than in L and BG pasta (19.1 and 18.9%, respectively).…”

“…BG pasta presented a significantly higher RAG and lower SAG than F and L pasta. This could be related to its lower aggregated protein network (SE-HPLC results) and smaller starch granules (microscope observation), two parameters that have been shown to increase starch digestibility [17, 65]. In addition, the black-gram starch has been reported to have a lower molecular weight of amylose and amylopectin than lentil starch, increasing its in-vitro glycemic index [65].…”

“…Legumes are rich in proteins (20–37%, w/w) [10] easily available [11], rich in dietary fibers (3–31% w/w) [12] and in resistant starch (RS, 11–20% w/w) [13]. The in-vitro and the in-vivo glycemic index can be reduced or maintained at its low value in legume enriched pasta [14–17] in comparison to their no-legume counterparts. In addition, legumes are also known to lower blood cholesterol and triglycerides [11].…”