Effect of shape, gluten, and mastication effort on in vitro starch digestion and the predicted glycemic index of pasta

Gluten-containing (GC) and gluten-free (GF) pasta consumption has been growing in recent years. The market offers a wide variety of pasta types, with differences in shape and formulation that influence the mastication process and, consequently, their nutritional behaviors (i.e. starch digestibility and glycemic response). This study investigated the effect of shape, gluten, and structural breakdown on in vitro starch digestibility and predicted the glycemic index (pGI) of GC and GF penne, spaghetti, and risoni. Pasta was cooked and minced to mimic short, intermediate, and long mastication efforts. Short mastication led to a higher number of big particles than intermediate and long mastications for all pasta samples, which was reflected in the different starch digestibility and pGI patterns. Multivariate analysis of variance showed that the three studied factors differently affected the in vitro starch digestion of pasta. Mastication effort, shape, and their interaction mainly affected the starch digestion rate and pGI. Gluten was the major factor in affecting the amount of digested starch. The results suggested that small shapes (i.e. risoni), the presence of gluten, and short mastication effort led to a lower pGI. The findings will be useful for the development of pasta products tailored to fulfill the needs of specific consumers following a rational food design approach.