Improving the quality of dough obtained with old durum wheat using hydrocolloids

In Mediterranean countries, and in Sardinia in particular, durum wheat is traditionally used for bread production and modern cultivars have gradually replaced the use of old landraces due to the poor technological quality of the latter. However, recent escalation in customer demand for old varieties thanks to an appreciation of their nutritional properties, as well as ecological issues, has led to the need for technological improvements able to enhance the rheological performance of the old varieties to support their diffusion. The aim of this study was to assess whether the baking performance of an Old Italian wheat cultivar, Russello wheat, could be improved through the addition of different hydrocolloids (methylcellulose, guar, psyllium, xanthan and tara). The effects of two different concentrations (0.5% and 1%) of each hydrocolloid on the rheological properties, pasting, fermentation and microstructural properties of dough were assessed, and the results compared with those obtained using a modern durum wheat cultivar flour. Significant differences were found in the dough obtained with hydrocolloids. In particular, dough extensibility was increased with 1% psyllium or xanthan gum, whereas the gas retention coefficient was increased with all hydrocolloids. The pasting properties were modified via an increase in the final viscosity and setback value compared with control semolina (with the exception of methylcellulose); this resulted in a more homogeneous dough structure with a compact appearance and the absence of any deep interruptions in the gluten network as revealed by scanning electron microscopy.