Analysis of vitamins A, E and C, iron and selenium contents in infant milk-based powdered formula during full shelf-life

The stability of vitamins A, E and C, and the iron and selenium content were determined in two types of long chain-polyunsaturated fatty acid (LC-PUFA) supplemented milk-based powdered infant formulas (IF), during an 18-month storage period at 25 and 40 degrees C. The first type (IF-A) was supplemented with vitamin A as retinol acetate. The second type (IF-B) was supplemented with vitamin A as retinol palmitate. Both types were also supplemented with vitamin E as alpha-tocopherol acetate and with vitamin C as ascorbic acid. The two formulas studied had higher vitamin A (140% and 139%), vitamin E (109% and 198%) and vitamin C (167% and 118%), but lower iron (65.0% and 65.3%) and selenium (72.9% and 79.4%) than the amounts declared on the label. As expected, all the studied vitamins showed decreases during storage, and these decreases were higher in formulas stored at 40 degrees C. The losses of vitamin A at 40 degrees C after 18 months of storage were 27.5% in IF-A and 29% in IF-B, while vitamin E losses under the same conditions were 23.1% and 28.1%, and vitamin C losses under the same conditions were 28.4% and 48.6%. All these losses justify the over-fortification of the aforementioned vitamins in these LC-PUFA supplemented IFs. Iron and selenium content remained unchanged throughout storage. (c) 2007 Elsevier Ltd. All rights reserved.