Solvation behavior and sweetness response of carbohydrates, their derivatives and sugar alcohols in thiamine HCl (vitamin B1) and pyridoxine HCl (vitamin B6) at different temperatures

•Transfer volumes for vitamin B1 are higher than vitamin B6.•Hydrophilic interactions exist between vitamins and solutes.•Carbohydrates/derivatives exhibit kosmotropic nature in water/cosolute solutions.•Sugar alcohols have higher partial molar volumes than their parent monosaccharides.•Absorbance shows hyperchromic shift in both aqueous (pH = 4.4)/buffer medium (pH = 9).

Volumetric properties are important tools to study the solvation behavior of solutes and reveal valuable information about solute-solute/cosolute interactions. Therefore, standard partial molar volumes at infinite dilution have been calculated from density measurements for monosaccharides, their methoxy and deoxy derivatives, disaccharides and sugar alcohols in (0.05, 0.15, 0.25 and 0.35) mol kg−1 thiamine HCl(aq) and pyridoxine HCl(aq) solutions over temperature range (288.15-318.15) K at pressure, p = 0.1 MPa. The corresponding transfer volumes, expansibilities and apparent massic volumes have been evaluated to examine the solvation behavior and the basic taste quality of studied solutes. UV-Vis absorption study of these solutes has also been carried out in 1.0 × 10−4 mol kg−1 thiamine HCl and pyridoxine HCl solutions. Results have been compared with our previously reported studies carried out in l-ascorbic acid (vitamin C). Stereochemical effects on hydration controlled by dominant conformations of studied solutes have also been discussed.