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Effect of coagulation and washing conditions on fines, water holding capacity and microstructure of acid casein curd

Published online by Cambridge University Press:  01 June 2009

Jaouad Fichtali
Affiliation:
Department of Food Science and Agricultural Chemistry, Macdonald College of McGill University, St Anne de Bellevue, Québec H9X 1CO, Canada
Frederik R. van de Voort
Affiliation:
Department of Food Science and Agricultural Chemistry, Macdonald College of McGill University, St Anne de Bellevue, Québec H9X 1CO, Canada
Christian J. Toupin
Affiliation:
Centre de recherches et de développement sur les aliments, Agriculture Canada, St-Hyacinthe, Québec J2S 8E3, Canada

Summary

Acid casein was prepared under various conditions of pH, concentration and wash regimens (temperature, time, agitation and wash water ratio) according to a response surface experimental design. The resulting product was analysed for water-holding capacity and loss of fines, and the structure of the curd assessed by scanning electron microscopy. Concentration, pH and temperature were the major factors in terms of influencing fines, water-holding capacity and the microstructure of the curd. Fines could be minimized by selecting appropriate pH, concentration and agitation conditions. The final moisture content of the curd was mainly controlled by pH, concentration and temperature and may aid in the selection of parameters to obtain good dewatcring and drying efficiencies. Microstructural analysis visualized the effects of pH, concentration, temperature and their interactions on the casein structural network and the effects of the process parameters are discussed in relation to those changes. Response surface methodology was shown to be an effective tool for examining which variables used in the process were significant and provided guidance as to the type of physicochemical mechanisms affecting the system.

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

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References

REFERENCES

Association Of Official Analytical Chemists 1984 Official Methods of Analysis of the AOAC, 14th edn.Arlington, VA: AOACGoogle Scholar
Barraquio, V. L., Fichtali, J., Ng-Kwai-Hang, K. F. & Van De Voort, F. R. 1988 Acid coagulation of skim milk powder by extrusion processing. Canadian Institute of Food Science and Technology Journal 21 305311CrossRefGoogle Scholar
Box, G. E. P. & Draper, N. R. 1987 Empirical Model-Building and Response Surfaces. New York: John Wiley and SonsGoogle Scholar
Bressan, J. A. & Hobman, P. G. 1985 Stage efficiency in continuous countercurrent casein washing systems. New Zealand Journal of Dairy Science and Technology 20 117127Google Scholar
Brulé, G., Maubois, J. L. & Fauquant, J. 1974 [Contents of mineral elements in products from ultrafiltered milk.] Lait 54 600615Google Scholar
Chou, D. H. & Morr, C. V. 1979 Protein-water interactions and functional properties. Journal of the American Oil Chemists' Society 56 53A62ACrossRefGoogle Scholar
Date, A. R. & Gray, A. L. 1989 Applications of Inductively Coupled Mass Spectrometry. New York: Applied Science PublishersGoogle Scholar
Fichitali, J., Van De Voort, F. R. & Khuri, A. I. 1990 a Multiresponse optimization of acid casein production. Journal of Food Process Engineering 12 247258CrossRefGoogle Scholar
Fichtali, J., Van De Voort, F. R. & Toupin, C. J. 1990 b Coagulation and washing conditions for acid casein production. International Journal of Food Science and Technology In pressCrossRefGoogle Scholar
Fox, P. F. 1982 Heat-induced coagulation of milk. In Developments in Dairy Chemistry-1: Proteins pp. 189228 (Ed. Fox, P. F.). London: Applied Science PublishersGoogle Scholar
Hobman, P. G. 1978 A model for predicting the water required to wash casein curd. New Zealand Journal of Dairy Science and Technology 13 229235Google Scholar
International Standards Organization 1980 Caseins and caseinates. Determination of lactose content – Photometric method. International Standard ISO-5548Google Scholar
Jablonka, M. S. & Munro, P. A. 1985 Particle size distribution and calcium content of batch-precipitated acid casein curd: effect of precipitation temperature and pH. Journal of Dairy Research 52 419428CrossRefGoogle Scholar
Jablonka, M. S. & Munro, P. A. 1986 a Development of an objective method for assessing the mechanical strength of casein curd. Journal of Dairy Research 53 6168CrossRefGoogle Scholar
Jablonka, M. S. & Munro, P. A. 1986 b Effect of precipitation temperature and pH on the continuous pilot-scale precipitation of acid casein curd. New Zealand Journal of Dairy Science and Technology 21 111123Google Scholar
Kinsella, J. E. 1984 Milk proteins: physicochemical and functional properties. CRC Critical Reviews in Food Science and Nutrition 21 197262CrossRefGoogle ScholarPubMed
Kinsella, J. E. & Fox, P. F. 1986 Water sorption by proteins: milk and whey proteins. CRC Critical Reviews in Food Science and Nutrition 24 91139CrossRefGoogle ScholarPubMed
Muller, L. L. 1971 Manufacture and uses of casein and co-precipitate. Dairy Science Abstracts 33 659674Google Scholar
Muller, L. L. 1982 Manufacture of casein, caseinates and co-precipitates. In Developments inDairy Chemistry-1: Proteins pp. 315337 (Ed. Fox, P. F.). London: Applied Science PublishersGoogle Scholar
O'Meara, G. M. & Munro, P. A. 1982 The precipitation and shrinkage of acid casein curd: a preliminary study. New Zealand Journal of Dairy Science and Technology 17 147159Google Scholar
Pearce, K. N., Johnstone, R. J. & MacColl, A. J. 1987 Computer simulation of continuous multi-stage countercurrent washing of casein curd. New Zealand Journal of Dairy Science and Technology 22 4966Google Scholar
Richert, S. H. 1975 Current milk protein manufacturing processes. Journal of Dairy Science 58 985993CrossRefGoogle Scholar
Southward, C. R. 1985 Manufacture and applications of edible casein products. L. Manufacture and properties. New Zealand Journal of Dairy Science and Technology 20 79101Google Scholar
Srilaorkul, S., Ozimek, L., Wolfe, F. & Dziuba, J. 1989 The effect of ultrafiltration on the physicochemical properties of retentate. Canadian Institute of Food Science and Technology Journal 22 5662CrossRefGoogle Scholar
Zadow, J. G. 1971 a Some theoretical aspects of casein washing: Part I. Australian Journal of Dairy Technology 26 913Google Scholar
Zadow, J. G. 1971 b Some theoretical aspects of casein washing: Part II. Australian Journal of Dairy Technology 26 1417Google Scholar