The present invention addresses the problem of providing a fat or oil composition which comprises an unsaturated fatty acid-containing fat or oil and yet enables the preparation of a nursery formulated milk with an excellent taste. The present invention has been completed based on the finding that oxidation of an unsaturated fatty acid is inhibited in a fat or oil composition wherein an aqueous phase, said aqueous phase containing one or more member selected from ascorbic acid and a salt thereof dissolved therein, having a pH value controlled to 3.6 or more and having a preset solid content, is dispersed in an oily phase, said oily phase comprising a fat or oil containing the unsaturated fatty acid and lecithin.
