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New equation for prediction of water activity in unripe cheese

Published online by Cambridge University Press:  01 June 2009

Pascual López
Affiliation:
Department of Food Science and Technology, Veterinary Faculty, University of Córdoba, 14005 Córdoba, Spain
Andrés Marcos
Affiliation:
Department of Food Science and Technology, Veterinary Faculty, University of Córdoba, 14005 Córdoba, Spain
María A. Esteban
Affiliation:
Department of Food Science and Technology, Veterinary Faculty, University of Córdoba, 14005 Córdoba, Spain

Summary

The water activity of fresh cheese made from cows', ewes' and goats' milk, as well as curd cheese and whey cheese, responds to the equation aw = 0·9719−0·0044[NaCl] + 0·0041 pH, with a square of multiple correlation coefficient R2 = 0·95. This equation was obtained by multiple regression analysis of data point sets of the variables x (g NaCl/100 g moisture), y (pH) and z (water activity, aw) determined as the average of values provided by six samples of each unripe product. Application of this equation to 30 individual samples of unripe dairy products investigated yielded calculated aw values within ±0·005 and ±0·002 aw units of the experimental water activities in 86·7% and 53·3% of the samples, respectively. These results are closer to the experimental values than those provided by earlier predictive equations.

Type
Original Articles
Copyright
Copyright © Proprietors of Journal of Dairy Research 1990

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References

REFERENCES

Alcalá, M., Esteban, M. A., Fernández-Salguero, J. & Marcos, A. 1989 [Calculation of water activity in yogurt.] Alimentaria 26 (206) 5557Google Scholar
Association Of Official Agricultural Chemists 1965 Official Methods of Analysis of the AOAC, 10th edn, Washington, DC: AOACGoogle Scholar
British Standards Institution 1963 Methods for the Chemical Analysis of Cheese, London: BSI (British Standard no. 770)Google Scholar
Esteban, M. A. & Marcos, A. 1990 Equations for calculation of water activity in cheese from its chemical composition: a review. Food Chemistry 35 179186CrossRefGoogle Scholar
Kosikowski, F. V. 1977 Cheese and Fermented Milk Foods, 2nd ed.New York: F. V. Kosikowski and AssociatesGoogle Scholar
Marcos, A. 1987 Spanish and Portuguese cheese varieties. In Cheese: Chemistry, Physics and Microbiology, vol. 2, Major cheese groups pp. 185219 (Ed. Fox, P. F.). London: Elsevier Applied ScienceGoogle Scholar
Marcos, A., Alcalá, M., Esteban, M. A., Fernández-Salguero, J., León, F., Beltrán, F. & Sanz, B. 1983 [Water activity of fresh cheeses.] Industrias Lácteas Españolas 5354, 5761Google Scholar
Marcos, A., Alcalá, M., León, F., Fernández-Salguero, J. & Esteban, M. A. 1981 Water activity and chemical composition of cheese. Journal of Dairy Science 64 622626CrossRefGoogle Scholar
Marcos, A., Fernández-Salguero, J., Esteban, M. A. & Alcalá, M. 1985 a Water activity measurement near to 1·00. Journal of Food Technology 20 523526CrossRefGoogle Scholar
Marcos, A., Fernández-Salguero, J., Esteban, M. A., León, F., Alcalá, M. & Beltrán, F. H. 1985 b [Spanish cheeses: Tables of composition, nutritive value and stability.] Córdoba, Spain: University of CórdobaGoogle Scholar
Robinson, R. A. & Stokes, R. H. 1959 Electrolyte Solutions, 2nd edn.London: ButterworthsGoogle Scholar
Rüegg, M. 1985 Water in dairy products related to quality, with special reference to cheese. In Properties of Water in Food (in Relation to Quality and Stability) pp. 603625 (Eds Simatos, D. and Multon, J. L.). Dordrecht: Martinus Nijhoff PublishersCrossRefGoogle Scholar