Hostname: page-component-77f85d65b8-hzqq2 Total loading time: 0 Render date: 2026-04-18T08:03:35.692Z Has data issue: false hasContentIssue false
  • English
  • Français

Formation of acid-heat-induced skim milk gels in the pH range 5·0–5·7: effect of the addition of salts and calcium chelating agents

Published online by Cambridge University Press:  01 June 2009

Simon J. Goddard  and
Mary-Ann Augustin
Simon J. Goddard
Affiliation:
CSIRO Division of Food Science and Technology, Melbourne Laboratory, Highett, VIC 3190, Australia
Mary-Ann Augustin
Affiliation:
CSIRO Division of Food Science and Technology, Melbourne Laboratory, Highett, VIC 3190, Australia
Get access Rights & Permissions [Opens in a new window]

Summary

The effects of pH and added salts or chelating agents on the gel strength and dynamic rheological properties of acid–heat-induced gels made from reconstituted skim milk (200 g solids/l) were investigated. Gel strength increased as pH was lowered between 5·75 and 5·15 except in the range pH 5·45–5·25 where a local maximum in gel strength was obtained at pH 5·35. Gel characteristics were affected by addition of salts or chelating agents but each of their effects was different, depending on the final pH of the milk gel. The addition of CaCl2 or chelating agents (Na2HPO4, disodium citrate or the disodium salt of EDTA) which affected micellar calcium phosphate, non-sedimentable casein and Ca2+ activity in different ways all resulted in decreased gel strength at pH 5·5. The addition of CaCl2 or MgCl2 caused a decrease in tanδ (ratio of the viscous modulus G″ to the elastic modulus G′) whereas disodium citrate or the disodium salt of EDTA addition caused an increase and Na2HPO4 addition did not cause a change. The addition of NaCl (up to 50 mM), which causes an increase in ionic strength but has no effect on non-sedimentable casein and Ca2+ activity, decreased gel strength but did not change tanδ. The addition of a range of other salts (KCl, NH4Cl, NaSCN, NaNO3 or Na2SO4) also decreased gel strength at pH 5·5.

Information

Type
Original Articles
Information
Journal of Dairy Research , Volume 62 , Issue 3 , August 1995 , pp. 491 - 500
Copyright
Copyright © Proprietors of Journal of Dairy Research 1995

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Article purchase

Temporarily unavailable

References

REFERENCES

Allen, R. J. L. 1940 The estimation of phosphorus. Biochemical Journal 34 858–865CrossRefGoogle ScholarPubMed
Augustin, M. -A. & Clarke, P. T. 1990 Effects of added salts on the heat stability of recombined concentrated milk. Journal of Dairy Research 57 213–226CrossRefGoogle Scholar
Banon, S. & Hardy, J. 1992 A colloidal approach of milk acidification by glucono-delta-lactone. Journal of Dairy Science 75 935–941CrossRefGoogle Scholar
Bohlin, L., Hego, P. -O. & Ljusberg-Wahren, H. 1984 Viscoelastic properties of coagulating milk. Journal of Dairy Science 67 729–734Google Scholar
Brings, N. A. & Kinsella, J. E. 1991 Effects of cations and anions on the rate of the acidic coagulation of casein micelles: the possible roles of different forces. Journal of Dairy Research 58 195–209CrossRefGoogle Scholar
Bringe, N. A. & Kinsella, J. E. 1993 Calcium chloride, temperature, preheat treatments and pH affect the rate of acid-induced aggregation of casein. Food Hydrocolloids 7 113–121Google Scholar
Byler, D. M. & Farrell, H. M. 1989 Infrared spectroscopic evidence for calcium ion interaction with carboxylate groups of casein. Journal of Dairy Science 72 1719–1723CrossRefGoogle Scholar
Dalgleish, D. C. 1984 Measurement of electrophoretic mobilities and zeta-potentials of particles from milk using laser Doppler electrophoresis. Journal of Dairy Research 51 425–438Google Scholar
Dalgleish, D. G. & Law, A. J. R. 1988 pH-induced dissociation of bovine casein micelles. I. Analysis of liberated caseins. Journal of Dairy Research 55 529–538Google Scholar
Damodaran, S. & Kinsella, J. E. 1982 Effects of ions on protein conformation and functionality. In Food Protein Deterioration—Mechanisms and Functionality, pp. 327–357 (Ed. Cherry, J. P.). Washington, DC: American Chemical SocietyCrossRefGoogle Scholar
Harwalkar, V. R. & Kalab, M. 1980 Milk gel structure. XI. Electron microscopy of glucono-δ-lactone- induced skim milk gels. Journal of Texture Studies 11 35–49Google Scholar
Harwalkar, V. R. & Kalab, M. 1981 Effect of acidulants and temperature on microstructure, firmness and susceptibility to syneresis of skim milk gels. Scanning Electron Microscopy no. 3 503–513Google Scholar
Heertje, I., Visser, J. & Smits, P. 1985 Structure formation in acid milk gels. Food Microstructure 4 267–277Google Scholar
Holt, C. 1992 Structure and stability of bovine casein micelles. Advances in Protein Chemistry 43 63–151CrossRefGoogle ScholarPubMed
Horne, D. S. & Davidson, C. M. 1986 The effect of environmental conditions on the steric stabilization of casein micelles. Colloid and Polymer Science 264 727–734CrossRefGoogle Scholar
Johnston, D. E. & Murphy, R. J. 1992 Effects of some calcium-chelating agents on the physical properties of acid-set milk gels. Journal of Dairy Research 59 197–208CrossRefGoogle Scholar
Kim, B. Y. & Kinsella, J. E. 1989 Rheological changes during slow acid induced gelation of milk by D-glucono-δ-lactone. Journal of Food Science 54 894–898Google Scholar
Lin, S. H. C., Leong, S. L., Dewan, R. K., Bloomfield, V. A. & Morr, C. V. 1972 Effect of calcium ion on the structure of native bovine casein micelles. Biochemistry 11 1818–1821CrossRefGoogle ScholarPubMed
Marier, J. R. & Boulet, M. 1958 Direct determination of citric acid in milk with an improved pyridine–acetic anhydride method. Journal of Dairy Science 41 1683–1692CrossRefGoogle Scholar
Pashley, R. M. & Quirk, J. P. 1989 Ion exchange and interparticle forces between clay surfaces. Soil Science Society of America Journal 53 1660–1667CrossRefGoogle Scholar
Pyne, G. T. 1962 Some aspects of the physical chemistry of the salts of milk. Journal of Dairy Research 29 101–130CrossRefGoogle Scholar
Roefs, S. P. F. M. 1986 Structure of Acid Casein Gels. A study of gels formed after acidification in the cold. PhD thesis, Agricultural University, Wageningen, The NetherlandsGoogle Scholar
Rollema, H. S. & Brinkhuis, J. A. 1989 A 1H-NMR study of bovine casein micelles; influence of pH, temperature and calcium ions on micellar structure. Journal of Dairy Research 56 417–425CrossRefGoogle ScholarPubMed
Rowland, S. J. 1938 The determination of the nitrogen distribution in milk. Journal of Dairy Research 9 42–46CrossRefGoogle Scholar
Schmidt, D. G., Koops, J. & Westerbeek, D. 1977 Properties of artificial casein micelles. I. Preparation, size distribution and composition. Netherlands Milk and Dairy Journal 31 328–341Google Scholar
Van Hooydonk, A. C. M., Hagedoorn, H. G. & Boerrigter, I. J. 1986 The effect of various cations on the renneting of milk. Netherlands Milk and Dairy Journal 40 369–390Google Scholar
Walstra, P. 1990 On the stability of casein micelles. Journal of Dairy Science 73 1965–1979CrossRefGoogle Scholar
White, J. C. D. & Davies, D. T. 1963 The determination of citric acid in milk and milk sera. Journal of Dairy Research 30 171–189Google Scholar
Zoon, P., Van Vliet, T. & Walstra, P. 1988 Rheological properties of rennet-induced skim milk gels. 3. The effect of calcium and phosphate. Netherlands Milk and Dairy Journal 42 295–312Google Scholar