A new method for the determination of vitamin D3 and 25-hydroxyvitamin D3 in meat

The total vitamin D content in meat, i.e., vitamin D3 and 25-hydroxyvitamin D3, was determined by HPLC after alkaline hydrolysation, solid-phase extraction and semi-preparative HPLC. For detection, a DAD detector between 220 and 320 nm was used and quantification was performed at 265 nm. Vitamin D2 was used as internal standard for vitamin D3 as well as for 25-hydroxyvitamin D3. Precision for vitamin D3 was determined in lean meat and lard to 9.1% and 7.1%, respectively. The corresponding values for 25-hydroxyvitamin D3 were 8.9% and 9.9%. Accuracy was determined in spiked samples, which showed a recovery of 94.7% and 99.0% for vitamin D3 and 25-hydroxyvitamin D3, respectively. The method is applicable for establishing data for food composition tables.