How combinations of dietary fibres can affect physicochemical characteristics of pasta

The production of high quality functional pasta from non-conventional raw materials represents a challenge. A partial substitution (15 g/100 g) of durum wheat semolina with long-chain inulin (HPX) and short-chain inulin (GR), Glucagel, psyllium and oat material (added individually and in combinations) was performed in order to increase the level of dietary fibre intake. The cooking, textural and colour characteristics of the pastas were evaluated and compared to control sample containing exclusively durum wheat semolina. Generally, material addition to the durum wheat pasta increased cooking losses, swelling index and water absorption, whilst reduced firmness and resistance to uniaxial extension of pastas. Raw spaghetti samples resulted significantly darker (L*) and more redness (a*) than control pasta. In the cooked pasta, all inulin enriched samples were brighter than semolina pasta. Pasta prepared with 15 g/100 g semolina of oat flour showed the best performance (except for the colour) compared to the other experimental pasta samples, but was significantly different to control durum wheat sample. Combinations of fibre rich additions were studied with the inclusion of inulin GR having a less deteriorating effect when added in combination with oat flour. This illustrates that some fibre rich sources may act better in combinations than separately.