Discrepancy on the quality characteristics of soluble dietary fiber in wild Rosa roxburghii Tratt fruits from different regions

To minimize waste and maximize the utilization of wild Rosa roxburghii Tratt fruits, the quality characteristics of soluble dietary fiber (SDF) extracted from wild Rosa roxburghii Tratt fruits sourced from ten regions were assessed in this study through an in-depth analysis. This analysis included the evaluation of chemical composition, physicochemical properties, structural elucidation, antioxidant capacity, and functional properties in yogurt applications. Communally, these SDFs are acidic heteropolysaccharides mainly composed of glucose, galacturonic acid, galactose, arabinose, and rhamnose, and all of them showed the infrared spectrum and high molecular weight (Mw) characteristics of polysaccharides. Meanwhile, the results indicated significant regional variations in the quality of SDF. Specifically, the SDF sourced from region LP possessed the highest arabinose glucose ratio (75.63%), Mw (312.488 kDa) and diffraction intensity. While the SDF sourced from region AZ indicated the lowest sugar content (41.57%) and diffraction intensity, but highest the swelling capacity (1.02 mL/g) and emulsion stability (41.90%). Furthermore, the SDF sourced from region ZS revealed the lowest Mw (149.476 kDa), total protein ratio (8.61%) and oil-holding capacity (1.63 g/g), but highest the total sugar ratio (58.63%). Additionally, the foaming capacity and DPPH free radical scavenging ability of SDF sourced from region TR were significantly superior to those of other regions (p < 0.05), and SDF sourced from region BD was also similar in terms of ABTS free radical scavenging rate and total protein proportion. Meanwhile, these SDFs' differences in surface morphological features and application properties in yogurt were also observed. These findings provide essential data for the further exploration of wild Rosa roxburghii Tratt and the enhancement of the quality of its soluble dietary fiber.