Abstract
The molecular bases of the equilibrium water activity concept are discussed and illustrated using some simplified examples. It is shown, using a relatively refined treatment, that at the moment we are not in a position to predict water activities, even for simple systems. A method is described which allows the prediction of the water activity of multicomponent systems from the properties of solutions containing one and two solutes. The method can also be used to predict solubilities in systems containing more than one solute, and this is illustrated with an example.
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References
K. Nelander, G. Olofsson, G.M. Blackburn, H.E. Kent, and T.H. Lilley, Aqueous solutions containing amino acids and peptides. Part 18. The enthalpy of solution of N-acetyl-L-phenylalaninamide in aqueous solutions containing formamide, Thermochimiea Acta 78:303 (1984).
P.J. Flory, Thermodynamics of high-polymer solutions, J. Chem. Phys. 9:660 (1941).
M.L. Huggins, Solutions of long-chain compounds, J. Chem. Phys. 9:440 (1941).
R.H. Stokes and R.A. Robinson, Solvation equilibria in very concentrated electrolyte solutions, J. Solution Chem. 2:173 (1973).
W.G. McMillan and J.E. Mayer, The statistical thermodynamics of multicomponent systems, J. Chem. Phys. 13:276 (1945).
See for example, T.H. Lilley, Physical properties of amino acid solutions, In: “The Chemistry and Biochemistry of the Amino Acids,” G.C. Barrett, ed., Chapman and Hall, London (1985).
G.M. Blackburn, T.H. Lilley, and E. Walmsley, Aqueous solutions containing amino acids and peptides. Part 13. Enthalphy of dilution and osmotic coefficients of some Af-acetyl amino acid amides and some N-acetyl peptide amides at 298.15 K, J. Chem. Soc. Faraday Trans. 1 78:1641 (1982).
T.H. Lilley, Criticism of a proposed corrected form of the Ross equation and a suggested extension of the equation, Int. J. Food Sci. Technol. 22:563 (1987).
R.H. Stokes and R.A. Robinson, Interactions in aqueous nonelectrolyte solutions. I. Solute-solvent equilibria, J. Phys. Chem. 70:2126 (1966).
K.D. Ross, Estimation of water activity in intermediate moisture foods, Food Technol. 29:26 (1975).
C.C. Briggs, R. Charlton, and T.H. Lilley, The osmotic coefficients of HClO4 — LiClO4 — NaClO4 mixtures, J. Chem. Thermodynamics 5:445 (1973).
See R.A. Robinson and R.H. Stokes, Activity coefficients in aqueous solutions of sucrose, mannitol and their mixtures at 25°C, J. Phys. Chem. 65:1954 (1961) for the references to earlier work.
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© 1991 Springer Science+Business Media New York
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Lilley, T.H., Sutton, R.L. (1991). The Prediction of Water Activities in Multicomponent Systems. In: Levine, H., Slade, L. (eds) Water Relationships in Foods. Advances in Experimental Medicine and Biology, vol 302. Springer, Boston, MA. https://doi.org/10.1007/978-1-4899-0664-9_16
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DOI: https://doi.org/10.1007/978-1-4899-0664-9_16
Publisher Name: Springer, Boston, MA
Print ISBN: 978-1-4899-0666-3
Online ISBN: 978-1-4899-0664-9
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