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Heat stability of milk: synergic action of urea and carbonyl compounds

Published online by Cambridge University Press:  01 June 2009

Samweul I. Shalabi  and
Patrick F. Fox
Samweul I. Shalabi
Affiliation:
Dairy and Food Chemistry Department, University College, Cork, Irish Republic
Patrick F. Fox
Affiliation:
Dairy and Food Chemistry Department, University College, Cork, Irish Republic
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Summary

Urea stabilizes milk to heat only in the presence of a carbonyl compound, such as a reducing sugar. Low molecular weight carbonyl compounds can increase stability in the absence of urea whereas larger molecules, e.g. hexoses and reducing disaccharides, cannot. However, the efficacy of all carbonyl compounds is increased considerably in the presence of urea. Aldehydes and ketones of similar molecular weights appear to be equally effective stabilizers. The optimum concentration of lactose in milk for stability was approximately 1% irrespective of urea concentration within the range 5–20 mM. However, modifying the lactose content of concentrated milks (approximately 8.5% protein) had little effect on heat stability.

Type
Original Articles
Information
Journal of Dairy Research , Volume 49 , Issue 2 , May 1982 , pp. 197 - 207
Copyright
Copyright © Proprietors of Journal of Dairy Research 1982

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References

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