Acoustic and volumetric analysis of potassium sorbate interactions with sodium/magnesium ascorbate in aqueous solutions at different temperatures

• This study investigates the volumetric and thermo-acoustic characteristics of antimicrobial agent, potassium sorbate in conjunction with sodium ascorbate/magnesium ascorbate, offering new insights into their intermolecular interactions. • Utilizing density and ultrasonic velocity measurements, significant solute-solvent interactions are revealed, demonstrating distinct hydrophilic, hydrophobic, and ion-hydrophilic behaviour under varying concentrations and temperatures. • Using Helper's thermodynamic relation is an effective approach for determining whether the ternary mixture behaves as a structure-maker or structure-breaker. • In addition to the coefficient of thermal expansion, the pair and triplet interaction coefficients shed light on the interactions between the combinations. • The results contribute valuable knowledge applicable to food preservation, pharmaceuticals, and cosmetics, advancing the understanding of how antioxidant salts interact with antimicrobial preservatives. This study evaluates the volumetric characteristics of potassium sorbate, an antimicrobial agent, along with the antioxidant salts sodium and magnesium ascorbate in aqueous solutions across four temperatures (288.15, 298.15, 308.15, and 318.15 K) and concentrations (0.0, 0.1, 0.4, and 0.7 mol.kg -1 ) at 0.1 MPa. Density and ultrasonic velocity were measured using the Anton Paar DSA 5000 M to calculate key thermodynamic parameters, including apparent molar volume ( V ϕ ) , partial molar volume ( V ϕ 0 ) , and partial molar volume of transfer ( Δ V ϕ 0 ) . Additionally, the apparent molar isentropic compression ( K ϕ , s ), partial molar isentropic compression ( K ϕ , s 0 ), and their transfer values ( Δ K ϕ , s 0 ) were computed to explore solute compressibility in the mixtures. The coefficients of thermal expansion, alongside pair and triplet interaction terms, provide insights into the interactions dynamics within the combinations. Furthermore, the temperature dependence of partial molar expansibility , ( ∂ E ϕ 0 / ∂ T ) P , helps determine whether the ternary system functions as a structure-maker or structure-breaker. These findings have significant implications for chemical engineering, materials science, and pharmaceutical applications.