In food-process engineering one of the main current objectives is related to exploiting the technological functionalities of food ingredients as well as their nutritional properties in order to develop innovative products with health-promoting aspects. Hence, an interesting active biological constituent in milk named caseinomacropeptide has received much attention. A method based on membrane technology is investigated to obtain caseinomacropeptide from milk. A process is used to remove whey proteins by microfiltration-diafiltration with ultrafiltration permeate; the resulting whey protein-free-milk is treated by chymosin in order to obtain a whey containing only CMP as protein. The impact of pH and temperature during the renneting process on the release of CMP has been investigated. To study the technological properties, in particular foaming and emulsifying properties of CMP, the whey is further clarified by microfiltration and concentrated by ultrafiltration. The experimental results open up new perspectives for the fractionation of CMP as well as for the use of CMP as a food-structuring agent.