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Compression and impact strength of gels, prepared from fractionated whey proteins, in relation to composition and microstructure

Published online by Cambridge University Press:  01 June 2009

Keith R. Langley  and
Margaret L. Green
Keith R. Langley
Affiliation:
AFRC Institute of Food Research, Reading Laboratory, Shinfield, Reading RG2 9AT, UK
Margaret L. Green
Affiliation:
AFRC Institute of Food Research, Reading Laboratory, Shinfield, Reading RG2 9AT, UK
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Summary

Gels varying in protein content and composition were prepared from whey proteins by a standard method and their compression and impact strengths were determined. No surface friction could be observed between the gels and the compression plates, and the Poisson's ratio was close to 0·5. Thus, the elastic moduli of the gels were determined. Compression and impact strengths and elastic moduli were related logarithmically to the β-lactoglobulin content of the protein powders. The strength and manner of fracture of the gels depended on the gel microstructure. Strong gels had a honeycomb structure consisting of a very tightly bound network, and failed by cracking on impact and by shear along cleavage planes in compression. Weaker gels had a loose open network with no definite means of fracture.

Type
Original Articles
Information
Journal of Dairy Research , Volume 56 , Issue 2 , May 1989 , pp. 275 - 284
Copyright
Copyright © Proprietors of Journal of Dairy Research 1989

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References

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