Effect of chestnut flour fortification on physico-chemical characteristics of gluten-free fresh pasta

Gluten-free (GF) products are typically characterised by lower nutritional and functional quality compared to gluten-containing counterparts. In the last years, several studies have tried to improve the nutritional characteristics of GF products by the utilisation of alternative ingredients. In this work, the effect of three levels of chestnut flour (CF) supplementation (20, 30, 40%) on the physico-chemical, sensory characteristics of raw and cooked GF fresh pasta, were investigated. CF showed higher water absorption properties (water binding capacity, solubility, absorption indexes) than the commercial GF mix used as control. In pasta, substitution of GF mix with CF caused a reduction in water activity and amount of freezable water due to stronger interaction of water molecules with CF components (sugars, starches, proteins). Increasing levels of CF also delivered darker, browner colour and a softer texture; the latter was also probably related to the greater cooking loss of CF, indicating a less organised network for the CF-enriched samples compared to the control. CF also improved the antioxidant capacity, due to the presence of bioactives in chestnut integuments. CF represents a valuable ingredient for the manufacturing of functional GF pasta, more appreciated in this study at a substitution level of 30% and 40%.