Gluten-free sorghum pasta: starch digestibility and antioxidant capacity compared with commercial products

Abstract

BACKGROUND: The development of new products with a focus on nutrition, rather than other technical aspects, is essential to improve the quality of celiac diets. Nutritional attributes of white and brown sorghum gluten-free pasta developed in a previous work were analyzed. The extent and kinetics of starch in vitro digestion, estimated glycemic index (eGI), potentially bioaccessible and dialyzable polyphenols, and antioxidant activity were evaluated and compared with commercial products. Results: Sorghum flour samples were used to obtain pasta with high protein (≈170 g kg −1 ), dietary fiber (≈80 g kg −1 ), polyphenols (2.6 g GA kg −1 pasta), and antioxidant activity. This sorghum pasta showed slower starch in vitro digestion than the other gluten-free pasta, with a high level of protein hydrolysis (76%). The highest eGI was observed in a rice sample (69.8) followed by a corn-based pasta (66.4). White and brown sorghum gluten-free pasta showed 2.9 and 2.4 times, respectively, higher potentially bioaccessible polyphenol content compared to that in cooked pasta. No significant variation in antioxidant activity was found in sorghum pasta after digestion and around 48% and 36% of activity was detected in dialysate. Conclusion: Both types of sorghum gluten-free pasta have demonstrated their nutritional value and represent a good potential alternative to current commercial pasta.