Abstract: In Algeria, the quantities of whey released into the environment are changing with the growth of the cheese industries whey remains a cheese effluent and a source of serious biological pollution due to its richness in noble organic fractions (lactose and proteins), released into the environment without prior treatment (case of cheese industry of Sidi Saada, Yellel, Relizane, Algeria) whey subsequently affects the quality of freshwater ecosystems (Oued Mina). The crude acid whey is a cheese rejection comes from the manufacture of soft cheeses and fresh dough. In this context, our study focused on the control of physicochemical and interfacial properties of demineralized acid whey. The results showed that demineralisation of crude acid whey modified its physicochemical and interfacial properties. In perspective, the valorization of industrial whey has become one of the major concerns of the cheese industries.