Effects of storage conditions on lipid oxidation in infant formulas based on several protein sources

The time course of several lipid oxidation parameters in infant formulas was the main focus of this study. Infant formulas based on different protein sources (milk protein, isolated soy protein, and hydrolyzed milk protein) were stored at different temperatures (32 and 55 degrees C) in sealed containers in air for 1 yr. Levels of thiobarbituric acid-reactive substances and 7-ketocholesterol, and losses of essential fatty acids and tocopherols were measured to monitor lipid oxidation. Tocopherol losses and 7-ketocholesterol concentrations were better lipid oxidation parameters than the others. Their concentration and losses depended on type of infant formula, storage temperature, and time.