Evaluation of Mineral Profile and Dietary Reference Intake from Collagen by ICP-Based Techniques

Recently, consumption of collagen-based foodstuffs has grown significantly, especially collagen hydrolysate, used as a dietary supplement. Information available on the content of essential and toxic elements in these products, however, is incipient. This study provides a novel assessment of the mineral profile (Al, As, Ca, Cd, Co, Cr, Fe, K, Mg, Mn, Na, P, S, V, and Zn) of collagen hydrolysate and gelatin by inductively coupled plasma optical emission spectrometry (ICP OES) and mass spectrometry (ICP-MS). Thirty-two samples were digested with diluted HNO 3 and H 2 O 2 , using an efficient microwave-assisted decomposition method (11.9% residual carbon content). The methodology was validated using certified reference materials and recovery tests, with agreement between the determined and certified/added concentration values (85–124%), and relative standard deviation of up to 18%. The limits of quantification ranged from 0.33 μg kg −1 (Cd) to 24 mg kg −1 (Na). The contributions of collagen hydrolysate to the Dietary Reference Intake values of the evaluated minerals were low, with the highest value being 13.5% for the Adequate Intake of Cr. The findings of Permitted Daily Exposure suggest that there is no risk of contamination with As and Cd by consuming this food supplement. Concentrations of Cr, Mn, and Zn reported on product labels agreed with experimental results. For Na, these values differed, indicating that a more rigorous quality control of collagen hydrolysate is necessary, in view of the health problems caused by excessive consumption of this element. Graphical abstract