Influence of the Chelation Process on the Stability of Organic Trace Mineral Supplements Used in Animal Nutrition.

The effect of the chelation process on the pH-dependent stability of organic trace minerals (OTMs) used as mineral supplements in animal nutrition was assessed using analytical techniques such as potentiometry, Fourier Transform Infrared Spectroscopy (FTIRS) and amino acid profiling. The aim was to understand the influence and relative importance of the manufacturing conditions on mineral chelation and the subsequent pH stability of OTMs. A selection of OTMs were assessed over a wide pH range to account for the typical environmental changes encountered in the gastrointestinal (GI) tract. In the case of proteinate type products, the potentiometric assessment of free mineral concentration indicated that the hydrolysis procedure used to generate the chelating peptides was the major influencer of the pH stability of the products. Many products are available under the umbrella term "OTMs", including amino acid complexes, amino acid chelates, polysaccharide complexes and proteinates. Significant differences in the pH-dependent stability of a range of commercially available OTMs were observed.