Two types of lucerne LPC were prepared by either adding the juice to hot water (85 °C) or by injecting steam until the juice reached a temperature of 85 °C after which the coagulum was freeze-dried. The resulting water and steam-coagulated LPG had a protein content of 54,5 and 49,9% and a lysine content of 3,22 and 2,92% respectively on an air-dry basis. The quality of the protein concentrates was determined by using the relative nutritive value (RNV) assay as well as in vivo true protein digestibility (PTD) with male Wistar rats. Body protein accretion was used as the measure of response to dietary protein and lactalbumin was used as the reference protein. The RNV's of lactalbumin, water-coagulated and steam-coagulated lucerne LPG were respectively 1,0; 0,573 and 0,397, whereas the PTO was respectively 97,6; 80,9 and 76,7%. All the rats on the water-coagulated lucerne LPC diet showed symptoms of photosensitivity.