Abstract Thermal treatments applied to the egg white cause undesirable modifications of their physicochemical and functional properties. The goal of this study was to acquire some knowledge on the effect of heat on some physico-chemical properties of the albumen while applying different scales (temperature / time). The results show: a sigmoïdale evolution with negative slope of the transmittance, an irreversible loss of solubility. Native-Page of protein's albumen shows the apparition of several bands what denotes diversity of proteins in egg white. The comparison of these profiles dealt to different temperatures /20 min with those unprocessed, shows apparition of new bands and different relative mobility due to the formation of aggregates. Coagulation and/or precipitation of these proteins have been observed around 74°C/20 min