Glycaemic index of some commercial gluten-free foods

Purpose: Gluten-free products present major challenges for the food industry in terms of organoleptic, technological and nutritional characteristics. The absence of gluten has been shown to affect starch digestibility, thus increasing the postprandial glycaemic response. However, in recent years, gluten-free technologies have been improved, thus possibly modifying this quality parameter. We investigated the glycaemic index (GI) of 10 commercial foods aiming to update the GI values of the most common gluten-free products consumed in Italy. Methods: The in vivo GI was evaluated for six bakery products and four types of pasta. The postprandial glucose response was obtained in two groups with 10 healthy volunteers each. Results: The overall GI values ranged from 37.5 for breakfast biscuits to 66.7 for puffed multigrain cake. Breads and pasta had GI values consistently lower than those previously reported in the literature. Conclusion: The present study showed that several commercial GF products exhibited low and medium GI values, not confirming the previous observations on the high GI of GF. However, considering the multiple formulations and processes for preparation of these products, further studies are recommended.