Abstract: The flowability, solubility, saponin dissolution rate and other physical properties of Camellia chrysantha (Hu) Tuyama flower powder in 3 different particle size ranges were determined, and the particle size and microstructure were measured with a particle size analyzer and a scanning electron microscope. The results showed that the particle size of ordinary, submicron and nanometer powder decreased sequentially with mean diameter of 133.90, 15.76 μm and 201.50 nm, respectively, and consequently the degree of cell disruption and the degree of irregularity increased with significant differences being observed among the three powders. Flowability, bulk density, wettability and expansibility decreased first and then increased with the decrease of particle size and the highest values of these parameters were recorded for the ordinary powder. The ordinary powder also had the highest water-holding capacity, followed by the submicron powder. Water solubility and saponin dissolution rate initially increased followed by a slight decrease. These findings suggested that the physical characteristics of Camellia chrysantha (Hu) Tuyama powder with different particle sizes were diverse. Overall, the submicron powder had high water solubility and saponin dissolution rate, and could be readily absorbed with high bioavailability in the body and conveniently processed, presenting good application prospects.

Key words: Camellia chrysantha (Hu) Tuyama, powder, particle size, physical characteristics