Chemical, physical and rheological properties of oat flour affected by the isolation of beta-glucan preparation

• Properties of a micronized oats flour, a by-product of β-glucan separation, were compared to commercial oat and wheat flours.
• Rheological properties of starches isolated from micronized and commercial oats flours and wheat flour were investigated.
• Micronization of oats flour caused decreased granularity and small changes in starch fraction.
• The role of β-glucans in controlling the properties of oats flour pastes is not decisive.

The aim of this study was to evaluate the effect of process called micronization, applied during preparation of beta-glucan concentrate, on properties of residual oats flour, and respective starch. The properties of residual oats flour (ROF) and starch isolated from this material (ROS) were compared with commercial flours: oats (COF) and wheat (CWF), and the respective starches (COS and CWS).It was shown, that micronization caused changes in starch fraction. Starch granules present in ROF not occur in clusters, and were only slightly damaged, which had no influence on molar mass of starch glucans, as well as on swelling and pasting properties of starch and mechanical modulus at linear viscoelasticity range. It was observed that flour pasting properties are determined not only by starch properties but also the presence other flour constituents (lipids, soluble and insoluble protein fractions, and to slightly lesser degree the content of beta – glucans).