Preparation of Functional Pasta Supplemented with Amaranth Pregelatinized Extruded Flour

Semolina pasta with improved nutritional properties is increasingly demanded by consumers. High protein content and low starch digestibility are features desired for a functional pasta. In this work, amaranth flour was used for 50% supplementation of semolina in pasta preparation. Raw amaranth flour increased protein from 11.7 g/100 g to about 14.0 g/100, dietary fiber from 6.8 g/100 g to about 8.0–10.0 g/100 g. However, raw amaranth flour deteriorated the texture of cooked pasta by increasing hardness from 15.7 to 52.8 N and reducing cohesiveness from 0.71 to 0.55. Pregelatinizations at 50 and 100% were explored to reduce the adverse effects of raw amaranth flour. The gelatinized amaranth flour mimicked the texture of semolina pasta, although cooking loss increased from 3.3 g/100 g to about 9.2 g/100 g, and the water absorption showed a marked reduction from 116.4% to about 80.0–84.0%. The in vitro starch digestibility was similar for pasta made with semolina and pasta containing pregelatinized starch, although digestibility decreased from 95 to 85% for raw amaranth flour. Overall, the results showed that amaranth flour offered advantages and drawbacks for the formulation of pasta with improved nutritional features.