Improving the cognitive function of an animal by providing a composition containing beta-casein, wherein at least 75% by weight of the beta-casein is a beta-casein variant that does not produce BCM-7 on digestion in the gut of the animal.藉著提供一種含有β-酪蛋白的組成物來增進動物的認知功能,在該組成物中,至少75重量%的β-酪蛋白是在動物消化道(gut)中消化時不會產生BCM-7的β-酪蛋白變異體。