Potential of water dropwort (Oenanthe javanica DC.) powder as an ingredient in beverage: Functional, thermal, dissolution and dispersion properties after superfine grinding

Dried water dropwort (Oenanthe javanica DC.) was treated by coarse and superfine grindings, respectively. Four particle sizes water dropwort powders (WDPs) of 250-150, 150-75, 75-38 and < 38 μm were sieved, then the corresponding particle size, color, chemical components, thermal, functional, dissolution and dispersion properties were investigated. Results showed that the surface area, greenness, brightness, and soluble dietary fiber contents of WDPs increased after superfine grinding. With the decreasing of particle sizes, the solubility, water holding and swelling capacities, as well as thermal stability increased significantly, while the oil holding capacity decreased. Fourier-transform infrared spectroscopy (FTIR) analysis indicated that the main chemical structures were not destroyed after superfine grinding. The dissolution of flavonoids, total polyphenols, soluble proteins and polysaccharides were improved gradually as particle sizes decreased. The ultrafine WDPs (<38 μm) exerted highest dispersibility in colloidal solutions, especially in the solution of xanthan gum, which could be valuable in the beverage developments.