The invention provides a protein composition containing a milk basic protein fraction and a stabilizing agent selected from the group consisting of soybean polysaccharide, xanthan gum, pectin, gum arabic, gum ghatti, carrageenan, locust bean gum, sodium caseinate, lecithin, and carboxymethyl cellulose. With this protein composition, the heat resistance of the milk basic protein fraction is significantly improved. This enables the protein composition and food, beverages, feedstuff and medicines produced from the protein composition to be subjected to heating at 90°C or higher without deactivating the milk basic protein fraction.一種蛋白質組成物，其含有：乳鹼性蛋白質級分，及選自於由大豆多醣類、三仙膠、果膠、阿拉伯膠、甘地膠、卡拉膠、刺槐豆膠、酪蛋白鈉、卵磷脂、羧甲基纖維素構成之群組中的至少1種安定劑。根據所述蛋白質組成物，可格外提升乳鹼性蛋白質級分之耐熱性。可在不使乳鹼性蛋白質級分失活下，對蛋白質組成物及包含該組成物的飲食品或飼料、醫藥於90℃以上進行加熱處理。
