Characterization of Durum-Wheat Pasta Containing Resistant Starch from Debranched Waxy Rice Starch

Durum wheat spaghetti samples prepared with increasing levels of resistant starch (RS) from debranched waxy rice starch (DWRS; i.e., 0, 5, 10, 15 g/100 g w/w) were analyzed for chemical composition, quality and sensory parameters and in vitro starch digestion. All the DWRS-containing spaghetti was "high in fibre", the dietary fiber content being > 6 g/100 g. In addition, spaghetti with the highest level of DWRS showed the highest RS content (p < 0.05), being 11.4 g/100 g dry matter. The starch hydrolysis index decreased (p < 0.05) as the level of DWRS increased, with a reduction of >20% comparing the 15-DWRS pasta to the control. DWRS had a negative impact on quality parameters, especially at higher DWRS levels. The use of DWRS shortened the optimal cooking time and impacted the samples' cooking loss, firmness, and stickiness. In addition, sensory analysis revealed differences among samples. However, irrespective of the level of DWRS in the recipe, the score for all attributes was > 5, which is considered the limit of acceptability. Substituting part of the semolina flour with DWRS increased the level of RS and the overall nutritional profile and affected the quality of semolina pasta, mainly at higher levels in the recipe.