Potential of microbial and cereal β-glucans as hydrocolloids in gluten-free oat baking

Abstract

To compensate the absence of viscoelastic gluten network, water-binding and viscosity-forming ingredients, hydrocolloids, are commonly used in gluten-free doughs. Currently, hydrocolloids are often E coded while many consumers prefer “clean-label” alternatives. For instance, microbial and cereal β-glucans are known to produce viscosity. In this study, the technological potential of these β-glucans as natural hydrocolloids was evaluated in gluten-free oat baking. Microbial β-glucan was produced by fermentation with P. claussenii using oat bran concentrate (OBC) as a raw material. Oat β-glucan was studied as various forms of OBC: as untreated OBC, pre-treated OBC suspension, and water-extractable fraction of OBC suspension (oat β-glucan extract). The baking properties after natural hydrocolloid additions were compared to a reference oat bread which was baked with common commercial hydrocolloids (psyllium, HPMC). The levels of hydrocolloids in the doughs were optimised by a test baking method. Among the hydrocolloids studied, the best bread properties were achieved with oat β-glucan extract as a hydrocolloid, as the breads resulted in similar specific volume and 37% lower staling rate compared to oat breads baked with commercial hydrocolloids. Thus, oat β-glucan extract provided a feasible and “clean-label” alternative for commercial hydrocolloids in gluten-free oat baking.