Dynamic high pressure microfluidization modified oat dietary fiber: Texture modulation and its mechanistic in whole grain oat milk

Oat dietary fiber (ODF) could product some undesirable textures such as rough and thick when added to food products, resulting the waste of resources. In this study, dynamic high pressure microfluidization (DHPM) was used to treat ODF in different pressures, and ODF was backfilled into whole grain oat milk (WOM) to investigate the efficiency of DHPM in improving the undesirable taste from ODF. The physicochemical properties and the microstructure of the DHPM-treated ODF were also determined to investigate the modification mechanism. The results showed that the WOM with DHPM-treated ODF conferred lower particle size (D[90] decreasing by 22.80%-51.35%), firmness (decreasing by 0.08%-9.84%), apparent viscosity and coefficient of friction, especially 120 and 150 MPa. Meanwhile, the samples with DHPM had higher sensory scores such as particles detected (swallowing and after swallowing increasing by 38.10%-85.71% and 29.17%-62.50% respectively), smoothness (increasing by 6.9%-27.59%), and mouth-coating, indicating that DHPM treatment could improve the undesirable texture brought by ODF. In addition, DHPM treatment reduced the particle size and insoluble dietary fiber content and fragmented microstructure of ODF, it may weaken the particles detected and improve the smooth taste. The consistency coefficient of ODF decreased from 0.0091 (0 MPa) to 0.0038 (150 MPa), which could be related to the improvement of texture flow and mouth-coating. In conclusion, WOM with DHPM-treatment ODF improved the undesirable texture such as roughness and stickiness, possibly associated with the ability of DHPM to alter the particle size, apparent viscosity and microstructure of ODF. This study provided the method of modification and utilization of ODF, and provided the idea and feasible solution for preparation of WOM.