Quantitative analysis of inositol phosphate contents in oat products using an anion exchange chromatographic method

Abstract

Oat has gained interest due to its high nutritional value. When utilising oat fractions rich in dietary fibre, their inositol phosphate (InsP, including phytate) content is considerably high due to the lack of active phytase in the kilned oat ingredients. The high InsP content is linked to decreased mineral absorption in the gut, but the mineral-binding ability of InsPs also results in antioxidativity and a decrease in starch hydrolysis, thus lowering glycaemic response. This study aimed to further develop an anion exchange liquid chromatographic method for quantification of different InsP forms from oat products and to study the changes in the InsP contents resulting from the differences in the ingredients or processes. The method was applicable for quantifying such InsP forms that can effectively bind minerals. The InsPs were stable at moderate temperatures and in the oat baking process, but a significant degradation occurred during the high-temperature treatments, extrusion, and bacterial fermentation.