Abstract: In order to make full use of calcium resources in bovine bone, waste long bone was chosen as raw materials, and the ultrasonic-assisted preparation technology was used to prepare calcium citrate. The optimum technological conditions for the preparation of calcium citrate from bovine bone was obtained using orthogonal test design based on the results of single factor test. Results showed that the calcium citrate with the best conversion rate of 71.2% can be prepared at 39°C for 21min under 320w ultrasonic power, 2:1 of critic acid and bone powder ratio, and 15:1 of solution and bone powder ratio. Compared with traditional methods, the dissolved calcium content prepared from bovine bone source using ultrasonic assisted method for 21 min was 84 times, 4.5 times and 3 times higher than the static method, stirring method and cooking method of reaction for 60 min, respectively. Besides, after three times of ultrasonic treatment, the conversion rate of calcium citrate was as high as 96.2%. These results confirmed that ultrasonic technology is an effective method for preparing dissolved organic calcium from bovine bone, which can provide reference for the industrial production of calcium products from waste bovine bone.

Key words: Bovine bone, Calcium citrate, Ultrasound, Response surface methodology