Ultrasonic and Volumetric Study of Glycols with an Aqueous Food Preservative (Potassium Sorbate)

This research explores the molecular interactions of glycols [(EG), (DG), and (TG)] within potassium sorbate, a food preservative. The density and speed of sound of these glycols in potassium sorbate solutions were examined across different temperatures (288.15 K to 318.15 K) at a pressure of 0.1 MPa and concentrations [(0.01, 0.02, and 0.03) mol/k \({\text{g}}^{-1}\)], density and speed of sound were measured by using the Anton Paar (DSA) 5000 M. From experimental data, properties like apparent molar volume (\({V}_{\varnothing }\)), partial molar volume (\({V}_{\phi }^{0}\)), apparent molar isentropic compressibility (\({K}_{\phi ,S}\))), partial molar isentropic compressibility (\({K}_{\phi ,S}^{0}\)), expansibility coefficients \({\left(\frac{\partial { E}_{\phi }^{0}}{\partial T}\right)}_{P}\), their transfer properties (Δ\({V}_{\phi }^{0}\), Δ\({K}_{\phi ,S}^{0}\)), and interaction coefficients (V_AB; V_ABB and K_AB; K_ABB, isobaric thermal expansion coefficients (\(\alpha )\) were estimated. These analyses aimed to investigate and comprehend the interactions among glycols [(EG), (DG), and (TG)] and potassium sorbate in aqueous solution, providing insights into solute–solvent interactions within ternary mixtures (potassium sorbate + water + (EG/DG/TG)). The study's conclusions are drawn from these solute–solvent interactions within the aqueous ternary mixture.