Studies on molecular interactions of some sweeteners in water by volumetric and ultrasonic velocity measurements at T = (20.0-45.0 °C)

Densities and ultrasonic velocity values for aqueous solutions of two sweeteners viz., maltose monohydrate and acesulfame-K have been measured as a function of concentration at 20.0-45.0 degrees C and atmospheric pressure. Solutions of acesulfame-K were treated as electrolyte, while maltose was considered as non-electrolyte. The apparent molar and specific volumes, their isentropic apparent molar and specific compressibilities, as well as their compressibility hydration numbers have been calculated and reported. Negative deviations from Debye-Huckel limiting law of apparent molar volume for acesulfame-K was obtained at given temperatures and can be used as a direct measure of the ion-ion and ion-solvent interactions. Furthermore, apparent specific volumes of the solutes were calculated and it was found that these values of the investigated solutes lie on the borderline between the values reported for sweet substances. The partial molar expansibility, its second derivative values, (partial derivative V-2(0)/partial derivative T-2) and thermal expansion coefficient have been estimated. (C) 2013 Elsevier Ltd. All rights reserved.