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An automatic method for measuring the heat coagulation time of milk powder solutions

Published online by Cambridge University Press:  01 June 2009

Helmut Foissy  and
Wolfgang Kneifel
Helmut Foissy
Affiliation:
Department of Dairy Research, Agricultural University, Vienna A-1180, Austria
Wolfgang Kneifel
Affiliation:
Department of Dairy Research, Agricultural University, Vienna A-1180, Austria
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Summary

An apparatus for the objective determination of the heat coagulation time of milk powder solutions is described. In the apparatus a chromium plated iron piston is moved by means of a ring magnet, driven by a control mechanism, through a heated cylinder containing a small sample of milk. When the milk coagulates, the increased impedance between the inner wall of the cylinder and the metal piston overcomes the magnetic strength of the ring magnet and the magnetic coil moves away from the piston core, resulting in a momentary change in coil current, which after amplification is used to stop a digital clock. The method was tested with 10 and 20 % milk powder solutions at various pH values, at temperatures of 120 and 140 °C. The results are comparable with those obtained using a traditional method involving visual determination of coagulation (Davies & White, 1966).

Type
Original Articles
Information
Journal of Dairy Research , Volume 51 , Issue 2 , May 1984 , pp. 325 - 329
Copyright
Copyright © Proprietors of Journal of Dairy Research 1984

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References

REFERENCES

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