The present study focused on evaluating the effect of meringue ingredients on the foaming properties of crude sweet whey. The experimental part included the preparation and physicochemical characterisation of crude sweet whey (pH, ash, proteins, lactose, dynamic viscosity, soluble solids), then the evaluation of the effect of meringue ingredients (crude white egg, table sugar and table salt) on the foaming properties of crude sweet whey by analysing its foaming capacity and air bubble diameter. On the physicochemical level, the physicochemical parameters of crude sweet whey are strongly linked to its origin and the operating modes of their analysis methods. On the functional level and in comparison to those obtained in crude sweet whey alone and mixed (crude sweet whey and 5% crude egg white), the best foaming properties (foaming capacity and foam stability) are those noted in the mixture which is composed of crude sweet whey and 100% crude egg white. The addition of table salt (0.5 and 1% NaCl) to the mixture (crude sweet whey and 100% crude egg white) reduced its foaming power (foam stability) over time. Compared to the 5% dose of table sugar, the addition of table sugar (200% sucrose) to the mixture (crude sweet whey and 100% crude egg white) improved its foaming power (foaming capacity and foam stability) over time. Thus, the addition of table sugar (200% sucrose) and table salt (0.5%NaCl) to the mixture (crude sweet whey and 100% crude egg white) simultaneously has improved its foaming power (foaming capacity and foam stability) over time. In conclusion, we can conclude on the one hand that the foaming properties of crude sweet whey are linked to its native physicochemical environment (individual system) and modified (mixed system: case of meringue ingredients), and on the other hand that crude sweet whey can constitute a key ingredient in the formulation of a new pastry product (meringue).