Preparation and Characterization of Ultrafine Fish Bone Powder

Ultrafine fish bone powder (UFBP) from silver carp (Hypophthalmichthys moli trix) was prepared using dry media milling. The characteristics of UFBP were investigated by a laser particle size analyzer, Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), and inductively coupled plasma (ICP) spectrometry. The size and specific surface area of UFBP particles were significantly (p < 0.05) affected by rotation speed, media/powder weight ratio, media diameter, and milling time. With the following conditions: rotation speed of 400 revolutions per minute, ratio of media to fish bone powder at 4:1, media diameter of 2 mm and 2.5 h of milling time, the optimal values of particle size (1.75 μm) and specific surface area (7.75 m2/g) were obtained. The SEM results confirmed that the particle became smaller and more uniform after milling treatment. Ash (63.71%) and protein (20.52%) were the main components of UFBP, and total calcium content was determined to be 236.90 mg/g in dried UFBP. As UFBP particle size decreased, calcium solubility significantly increased (p < 0.05), calcium content on the surface layer decreased, but the chemical compositions and structure did not change.