Artículos de revistas
Water Activity In Solutions Containing Organic Acids
Registro en:
Drying Technology. , v. 16, n. 9-10, p. 1789 - 1805, 1998.
7373937
2-s2.0-0032193542
Autor
Velezmoro C.E.
Meirelles A.J.A.
Institución
Resumen
A thermodynamic model for the activity coefficient was used to predict in some food-related solutions. Water activity values for organic acids solutions (malic, tartaric and citric) were measured experimentally and used to adjust interaction parameters for the UNIFAC model. The partial dissociation phenomenon for weak electrolytes in aqueous systems was considered and concentrations of species were calculated. Predictions of aw with mean deviations of 0.26% were obtained.A thermodynamic model for the activity coefficient was used to predict aw in some food-related solutions. Water activity values for organic acids solutions (malic, tartaric and citric) were measured experimentally and used to adjust interaction parameters for the UNIFAC model. The partial dissociation phenomenon for weak electrolytes in aqueous systems was considered and concentrations of species were calculated. Predictions of aw with mean deviations of 0.26% were obtained. 16 9-10 1789 1805 Abildskov, J., Constantinou, L., Gani, R., Towards the development of a second aproximation in activity coefficient models based on group contributions (1996) Fluid Phase Equilibria, (118), pp. 1-12 Achard, C., Gros, J.B., Dussap, C.G., Prédiction de l'activité de l'éau, des températures d'ébullition et de congélation de solutions aqueuses de sucres par un modèle UNIFAC (1992) Industries Alimentaires et Agricoles, 3 (109), pp. 93-101 Achard, C., Dussap, C.G., Gros, J.B., Prediction of pH in complex aqueous mixtures using a group-contribution method (1994) AIChE Journal, 7 (40), pp. 1210-1222 Achard, C., Dussap, C.G., Gros, J.B., Representation of vapour-liquid equilibria in water-alcohol-electrolyte mixtures with a modified UNIFAC group-contribution method (1994) Fluid Phase Equilibria, (98), pp. 71-89 Correa, A., Comesaña, J.F., Sereno, A., Measurement of water activity in water-urea-sugar and water-urea-polyol systems, and its prediction by the ASOG group contribution method (1994) Fluid Phase Equilibria, (98), pp. 189-199 Gmehling, J., Rasmussen, P., Fredeslund, A., Vapor-liquid equilibria by UNIFAC group contribution. Revision and extension. 2 (1982) Ind. Eng. Chem. Process Des. Dev., (21), pp. 118-127 Kuramochi, H., Noritomi, H., Hoshino, D., Nagahama, K., Representation of activity coefficients of fundamental biochemicals in water by the UNIFAC model (1997) Fluid Phase Equilibria, (130), pp. 117-132 Le Maguer, M., Mechanism and influence of water binding on water activity (1987) IFT Symposium Series, pp. 1-25. , Edited by Rockland L.B. and Beuchat L.R. Marcel Dekker Inc., N.Y. USA Oishi, T., Prausnitz, J.M., Estimation of Solvent Activities in Polymer Solutions Using a Group Contribution Method (1978) Ing. Eng. Chem. Process Des. Dev., 17, pp. 333-339 Pitzer, K.S., Electrolytes. From Dilute Solutions to Fused Salts (1980) Journal of the American Chemical Society, 9 (102), pp. 2902-2906 Prausnitz, J.M., Lichtenthaler, R.N., De Azevedo, E.G., (1986) Molecular Thermodynamics of Fluid-phase Equilibria, , Prentice-Hall Inc., N.J., USA Skjold-Jorgensen, S., Kolbe, B., Gmehling, J., Rasmussen, P., Vapor-liquid equilibria by UNIFAC group contribution. Revision and extension (1979) Ind. Eng. Chem. Process Des. Dev., 4 (18), pp. 714-722 Velezmoro, C., Meirelles, A.J., Modelagem e predição de atividade de água em pectinas usando metodos de contribuição de grupos: ASOG e UNIFAC (1996) Equipos y Procesos para la Industria de Alimentos (Anales del I Congreso Ibero-Americano de Ingenieria de Alimentos), 3, pp. 338-348. , Ortega, E., Parada, E. and Fito, P Velezmoro, C., Meirelles, A.J., Vitali, A., Prediction of water activity in solutions containing food additives (1997) Engineering & Food at ICEF 7, (1 PART), pp. A145-A148. , Edited by R. Jowitt