A membrane filtered soy protein isolate or concentrate can readily be blended with and hydrated by a dairy product, which is preferably liquid, such as milk and/or cream, at relatively low temperatures, e.g. below 30.degree. C. or even below 8.degree. C. The resulting blend can then be acted upon by a yoghurt-forming microorganism to produce a yoghurt-type product, which is comparable with an all dairy yoghurt in taste and mouthfeel.