Vegetable lecithins have been recommended for use as antioxygenic or stabilizing substances to delay rancidity in fats and oils, although complete experimental evidence as to their efficacy is lacking. Measuring the induction period of the oxidation of lard by means of the oven-test, two commercial samples of soy-bean lecithin were shown to be weak antioxidants, having indices of 1.7 and 1.8 respectively