Survey of Inositol in Infant Formula

Abstract : Results of free and bound myo-inositol in infant formula (IF) are presented. Inositol was analyzed by HILIC ultra-performance liquid chromatography coupled with mass spectrometer. The levels of free myo-inositol in 27 Australian and 4 EUoriginated IF samples were 300-600 mg/kg of powder or 1.6-3.1 mg/100 kJ. The amount of bound inositol in lipid fraction of IFwas, on average, 10% of free myo-inositol.Keywords : infant formula, myo-inositol, survey, UPLC-MS/MS. Introduction Inositol is an important nutrient present naturally inhuman milk and cow’s milk but in a lesser quantity. It existspredominantly in the free myo-inositol form. myo-Inositol isfound in large amounts in plant materials such as soy beansbut is in the bound form, predominantly as polyphosphate andin a lesser extent as phosphatidylinositol.The levels of inositol in infant formula are regulated.CODEX 1 defines lower and upper levels of inositol at 1 and9.5 mg/100 kJ. In the USA there is no prescribed limits 2 forinositol in dairy-based IF. The minimum amount of inositolin non-dairy based IF according to the Code of FederalRegulations (CFR) is 4 mg/100 kcal (~1 mg/100 kJ) and theupper limit is not regulated. The levels of inositol in IF inAustralia and New Zealand are regulated by the FSANZ2.9.1 and in China by the GB 10765-2010 Food Standards,Table 1.There are nine isomers of inositol C