Hostname: page-component-8448b6f56d-m8qmq Total loading time: 0 Render date: 2024-04-20T06:49:30.329Z Has data issue: false hasContentIssue false
  • English
  • Français

Use of Platelet Aggregometer to monitor the chymosin-initiated coagulation of casein micelles

Published online by Cambridge University Press:  01 June 2009

Neal A. Bringe  and
John E. Kinsella
Neal A. Bringe
Affiliation:
Institute of Food Science, Cornell University, Ithaca, NY 14853, USA
John E. Kinsella
Affiliation:
Institute of Food Science, Cornell University, Ithaca, NY 14853, USA
Get access Rights & Permissions [Opens in a new window]

Summary

The chymosin-initiated coagulation of casein micelles was followed by monitoring light transmission using a Platelet Aggregometer. The release of macropeptide by chymosin was monitored using fluorescamine. The lag period in the clotting reaction was proportional to clotting time and the reciprocal of enzyme concentration. The average rate of coagulation, which was approximately equal to the reciprocal of clotting time (Tc), increased in proportion to enzyme concentration at low enzyme concentrations and reached a limiting value at high enzyme concentrations. The percentage hydrolysis at the Tc was 47 ± 5% in the presence of 20 mM-CaCl2 and it was calculated that a 5-fold decrease in the speed of the enzyme-catalysed reaction would decrease this value at the Tc to 43 ± 5%. The possible uses and limitations of the Platelet Aggregometer for determining the influence of the chemical environment on the velocity of the chymosin-catalysed reaction and para-casein micelle aggregatability are discussed.

Type
Original Articles
Information
Journal of Dairy Research , Volume 53 , Issue 3 , August 1986 , pp. 359 - 370
Copyright
Copyright © Proprietors of Journal of Dairy Research 1986

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.)

References

REFERENCES

Beeby, R. 1980 The use of fluorescamine at pH 6·0 to follow the action of chymosin on º-casein and to estimate this protein in milk. New Zealand Journal of Dairy Science and Technology 15 99–108Google Scholar
Berridge, N. J. 1952 An improved method of observing the clotting of milk containing rennet. Journal of Dairy esearch 19 328–329CrossRefGoogle Scholar
Bringe, N. A. & Kinsella, J. E. 1986 Influence of calcium chloride on the chymosin-initiated coagulation of casein micelles. Journal of Dairy Research 53, 371–379CrossRefGoogle Scholar
Brinkhuis, J. & Payens, T. A. J. 1984 The influence of temperature on the flocculation rate of renneted casein micelles. Biophysical Chemistry 19 75–81CrossRefGoogle ScholarPubMed
Carlson, A. 1983 The enzymatic coagulation of milk. Ph.D. Thesis, University of Wisconsin, Madison, WI, USA. (Dissertation Abstracts International B 43 3671)Google Scholar
Chaplin, B. & Green, M. L. 1980 Determination of the proportion of º-casein hydrolysed by rennet on on cagulation of skim-milk. Journal of Dairy Research 47 351–358CrossRefGoogle Scholar
Dalgleish, D. G. 1979. Proteolysis and aggregation of casein micelles treated with immobilized or soluble chymosin. Journal of Dairy Research 46 653–661CrossRefGoogle Scholar
Dalgleish, D. G. 1980 A mechanism for the chymosin-induced flocculation of casein micelles. Biophysical Chemistry 11 147–155CrossRefGoogle ScholarPubMed
Dalgleish, D. G. 1983 Coagulation of renneted bovine casein micelles: dependence on temperature, calcium ion concentration and ionic strength. Journal of Dairy Research 50 331–340CrossRefGoogle Scholar
Dalgleish, D. G., Payens, T. A. J. & Brinkhuis, J. 1981 The rate constants for the aggregation of rennet-treated casein micelles. Netherlands Milk and Dairy Journal 35 381–383Google Scholar
Darling, D. F. & Van Hooydonk, A. C. M. 1981 Derivation of a mathematical model for the mechanism of casein micelle coagulation by rennet. Journal of Dairy Research 48 189–200CrossRefGoogle Scholar
Ekstrand, B., Larsson-Raznikiewicz, M. & Perlmann, C. 1980 Casein micelle size and composition related to the enzymatic coagulation process. Biochimica et Biophysica Acta 630 361–366CrossRefGoogle Scholar
Fox, K. K., Holsinger, V. H., Posati, L. P. & Pallansch, M. J. 1967 Separation of β-lactoglobulin from othermilk serum proteins by trichloroacetic acid. Journal of Dairy Science, 50 1363–1367CrossRefGoogle Scholar
Garnot, P. & Olson, N. F. 1982 Use of oscillatory deformation technique to determine clotting times and rigidities of milk clotted with different concentrations of rennet. Journal of Food Science 47 1912–1915CrossRefGoogle Scholar
Green, M. L., Hobbs, D. G., Morant, S. V. & Hill, V. A. 1978 Intermicellar relationships in rennet-treated separated milk. II. Process of gel assembly. Journal of Dairy Research 45 413–422CrossRefGoogle Scholar
Hardy, J. & Fanni, J. 1981 Application of reflection photometry to the measurement of milk coagulation. Journal of Food Science 46 1956–1957CrossRefGoogle Scholar
Hardy, J., Fanni, J. & Weber, F. 1981 [Study of milk coagulation by means of diffuse reflexion photometry.] Sciences des Aliments 1 351–364Google Scholar
Kovács-Proszt, G. & Sanner, T. 1973 Comparison of the specificity and kinetic properties of 3 milk-clotting enzymes. Journal of Dairy Research 40 263–272CrossRefGoogle ScholarPubMed
Marshall, R. J. & Green, M. L. 1980 The effect of the chemical structure of additives on the coagulation of casein micelle suspensions by rennet. Journal of Dairy Research 47 359–369CrossRefGoogle Scholar
Marshall, R. J., Hatfield, D. S. & Green, M. L. 1982 Assessment of two instruments for continuous measurement of the curd-firming of renneted milk. Journal of Dairy Research 49 127–135CrossRefGoogle Scholar
McMahon, D. J. & Brown, R. J. 1982 Evaluation of Formagraph for comparing rennet solutions. Journal of Dairy Science 65 1639–1642CrossRefGoogle Scholar
McMahon, D. J., Brown, R. J. & Ernstrom, C. A. 1984 a Enzymatic coagulation of milk casein micelles. Journal of Dairy Science 67 745–748CrossRefGoogle Scholar
McMahon, D. J., Brown, R. J., Richardson, G. H. & Ernstrom, C. A. 1984 b Effects of calcium, phosphate, and bulk culture media on milk coagulation properties. Journal of Dairy Science 67 930–938CrossRefGoogle Scholar
Mattarella, N. & Richardson, T. 1982 Adsorption of positively-charged β-lactoglobulin derivatives to casein micelles. Journal of Dairy Science 65 2253–2258CrossRefGoogle Scholar
Overbeek, J. Th. 1952 In Colloid Science (Ed. Kruyt, H. R.) vol 1, p. 302. Amsterdam: Elsevier Publishing Co.Google Scholar
Payens, T. A. J. 1977 On the enzymatic clotting processes II. The colloidal instability of chymosin-treated casein micelles. Biophysical Chemistry 6 263–270CrossRefGoogle ScholarPubMed
Payens, T. A. J. 1982 a Stable and unstable casein micelles. Journal of Dairy Science 65 1863–1873CrossRefGoogle ScholarPubMed
Payens, T. A. J. 1982 b About the change of the flocculation constant of micellar paracasein during rennet coagulation of milk. 21st International Dairy Congress, Moscow 2 233Google Scholar
Pierre, A. 1983 [Influence of a change in micellar charge on the proportion of caseinomacropeptide released by rennet on coagulation of milk]. Lait 63 217–229CrossRefGoogle Scholar
Scott Blair, G. W. & Oosthuizen, J. C. 1961 A viscometric study of the breakdown of casein in milk by rennin and rennet. Journal of Dairy Research 28 165–173CrossRefGoogle Scholar
Sommer, H. H. & Matsen, H. 1935 The relationship of mastitis to rennet coagulability and curd strength of milk. Journal of Dairy Science 18 741–749CrossRefGoogle Scholar
Tokita, M., Hikichi, K., Niki, R. & Arima, S. 1982 Dynamic viscoelastic studies on the mechanism of milk clotting process. Biorheology 19 209–219CrossRefGoogle ScholarPubMed