Functional properties and predicted glycemic index of gluten free cereal, pseudocereal and legume flours

Most of gluten free (GF) bakery products available on the market are made by a restricted number of grains. Flours and starches from rice and maize are mainly used. For this reason, people affected by celiac disease frequently suffer of nutritional deficiencies and have high intake of some nutrients. The use of a wider range of GF flours, rich in nutrients and phytochemicals, may improve the nutritional quality of GF products. This study aimed at the characterization of twelve GF flours obtained from cereals, pseudocereals and legumes for what concerns their functional properties, starch composition, phenolic and flavonoid content, and their effect on glycemic index (GI), that was estimated in vitro. In particular, starch composition had an influence on predicted glycemic index (pGI). pGI and damaged starch were positively related, whereas flavonoid, amylose and resistant starch (RS) contents were negatively related to pGI. In general, for all the parameters considered, cereals, except for rice flour, showed similar behavior, so as legumes. On the contrary, pseudocereals presented quite different characteristics between each other, due to their different botanical origin. The knowledge of starch composition, its relationship with GI, and functional properties could contribute to the selection of flours for healthier GF bakery products.