EFFECT OF FREE FATTY-ACIDS ON THE AMOUNT OF DEPOSIT FORMED FROM MILK ON HEATED SURFACES

Individual fatty acids were added to liquid skim-milk and to reconstituted dried skim-milk in concentrations similar to those produced by natural lipolysis, and their effects on deposit formation from the milk on a heated surface were determined. The use of reconstituted dried skim-milk considerably improved the reproducibility of the results. Butyric, caproic and caprylic acids did not influence the amount of deposit formation. Capric acid had a marked effect in reducing deposit at low concentrations : the effect of ageing of milk in reducing deposit formation is thought to be due to capric acid development. Lauric, myristic and palmitic acids had a slight effect, increasing deposit formation, while stearic acid caused a considerable increase. Capric acid was found to adsorb to the casein micelles in milk, and it may therefore act by interfering with casein aggregation during the build-up of deposit. © 1979, Proprietors of Journal of Dairy Research. All rights reserved.