The influence of a (1→3)(1→4)-β-D-glucan rich fraction from barley on the physico-chemical properties and in vitro reducing sugars release of durum wheat pasta

The effect of the addition of a beta-glucan fibre fraction from barley to durum wheat pasta was evaluated in terms of cooking characteristics, structure, texture and in vitro starch digestibility. Barley beta-glucan (BBG) fibre fraction was incorporated into pasta at 2.5%, 5%, 7.5% and 10% inclusion rates. Incorporation of the BBG fibre fraction to pasta attenuated reducing sugar release during in vitro digestion, the magnitude of reduction being related to the level of BBG fibre fraction inclusion. Changes to pasta cooking quality and texture were observed with BBG fibre fraction addition, including greater solid loss during cooking, increased pasta swelling and loss of hardness compared with the control pasta. Investigation of pasta microstructure and characterisation of starch gelatinisation events indicated that a combination of changes to the starch-protein matrix and the high water binding capacity of beta-glucan alters the physico-chemical properties and digestibility of the pastas.