Dates Events 1867 A formula containing wheat flour, cow's milk, malt flour, and potassium bicarbonate was developed.[105] 1915 A powder form of infant formula was introduced, containing cow's milk, lactose, oleo oils, and vegetable oils.[105] 1929 Soy formula was introduced.[105] 1935 Protein was added because it was believed cow's milk protein content was lower than human milk protein content; protein at 3.3–4.0 g/100 kcal was added.[105] 1959 Iron fortification was introduced because a large amount of iron (~80%) is used to expand the red blood cell mass in a growing infant.