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The biggest challenge in the production of gluten-free baked products is creating a structure without gluten while maintaining physicochemical and sensory properties. The aim of this study was to evaluate the possibility of applying oat β-glucan as the thickening and structure-making agent instead of xanthan (control sample), due to its pro-health technological properties, in yeast-leavened gluten-free cake. Thus, high-in-β-glucan oat fibre powder was incorporated into cake formulations as 5, 10, 15 and 20% replacement of rice or corn flour. The complex analysis of physicochemical and sensory properties was conducted, where texture and rheological aspects were the most important. An analysis of the correlation between rheological and physical properties was also conducted. Corn and rice cakes differed, but the results showed the increase of β-glucan, total dietary fibre, springiness, cohesiveness, storage (G') and loss (G″) modulus and the decrease of firmness and lightness. Improvement of porosity and volume was also noticed. Significant correlation was observed among G', G″, specific volume and texture components. Accelerated texture changes were noticed after 24 h of storage. To sum up, it is justified to incorporate oat fibre into gluten-free baked products, both to increase nutritional value and improve cake structure.

In this study, β-glucan was extracted from wholegrain oat and barley flours by a novel extraction and purification method employing natural flocculants (chitosan, guar gum and gelatin). The use of flocculants decreased the total amount of extracted gum, which was highest in control samples (9.07 and 7.9% for oat and barley, respectively). The β-glucan specific yield, however, increased with the use of chitosan and guar gum, which were able to remove protein and ash impurities resulting in gums with a higher purity.The highest concentration of chitosan (0.6 %) resulted in gums with the highest β-glucan content (82.0 ± 0.23 and 79.0 ± 0.19 for barley and oat, respectively) and highest β-glucan specific yield (96.9 and 93.3 % for oat and barley, respectively). Explanation is in R&D section. The use of gelatin was not successful. All gum samples had a high content of total dietary fiber (>74%) and a high water holding capacity (4.6-7.4 g/g), but differed in apparent viscosity, which was highest for the oat sample extracted with 0.6% chitosan. This sample also showed the highest β-glucan molecular weight among the oat samples, which were in general 10-fold higher than for the barley samples. Among the barley samples, β-glucan molecular weight was highest for the control., (Copyright © 2018 Elsevier Ltd. All rights reserved.)