PROBLEM TO BE SOLVED: To provide a method for reducing bitterness belonging to food products, pharmaceuticals, or cosmetics.SOLUTION: The method for reducing bitterness includes using an acid modification-processed egg obtained by mixing an organic acid solution and an egg to acid-modifying a protein part of the egg by the organic acid solution where the organic acid in the organic acid solution is not limited if it is edible such as lactic acid, succinic acid, fumaric acid, malic acid, acetic acid, tartaric acid, adipic acid, ascorbic acid, and a mixed organic acid thereof. In the method for preparing an acid modification-processed egg, the egg is a whole raw egg, a raw egg yolk, a raw egg white, and a mixture thereof or a frozen or cold stored substance thereof obtained by poultry such as chickens, ducks, and quails, and the pH of the acid-modified egg obtained by acid modification processing is 3-6, preferably 3.5-4.5.SELECTED DRAWING: NoneCOPYRIGHT: (C)2018,JPO&INPIT【課題】食品、医薬品又は化粧品が有する苦味を低減することができる苦味低減方法の提供。【解決手段】有機酸溶液と卵を混合処理し、卵の蛋白部分を有機酸溶液により酸変性させたもので、有機酸溶液における有機酸は、食用に供するものであれば特に制限はなく、例えば、乳酸、コハク酸、フマル酸、リンゴ酸、酢酸、酒石酸、アジピン酸、アスコルビン酸等及びこれらの混合有機酸等が挙げられる、酸変性処理卵を用いる苦味低減方法。前記卵は、鶏、うずら、あひる等の家禽類より得られる生全卵、生卵黄、生卵白又はこれら混合物、或いは冷凍又は冷蔵したもの等で酸変性処理により得られた酸変性卵のpHは3~6、好ましくは3.5~4.5である酸変性処理卵の調理方法。【選択図】なし