Inhibition of the Antibacterial Lactoperoxidase-Thiocyanate-Hydrogen Peroxide System by Heat-Treated Milk

B Ekstrand1, W M A Mullan1, A Waterhouse1

  • 1Department of Dairy Technology, West of Scotland Agricultural College, Auchincruive, Ayr, U. K.

The antibacterial system, lactoperoxidase-H2O2-SCN- was affected by the presence of heated milk or skim milk reconstituted from powders having received severe heat treatment. This inhibitory effect was related to the increase in exposed sulfhydryl groups and to the redistribution of protein between micellar and whey phases. Chromatographic analyses of heat-treated milk showed that the inhibitory factor was associated with the casein micelle fraction. The inhibition, however, was overcome by addition of unheated skim milk.

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