MIXTURES OF PALM KERNEL OIL WITH COCOA BUTTER AND MILK-FAT IN COMPOUND COATINGS

Thermal behavior of binary mixtures of palm kernel oil (PKO), cocoa bu tter (CB), and anhydrous milk fat was used to study mixed-lipid crysta llization. This study was related to the physical properties of compou nd coatings made with these fats. Phase behavior was studied by evalua ting changes in melting behavior with composition and time, by creatin g isosolid diagrams, and by monitoring polymorphic behavior. For binar y mixtures, multiple melting peaks and eutectic formation were observe d for 30-50% addition levels of CB to PKO, but not for addition of mil k fat to PKO. For compound coatings and binary mixtures, made with the same fat composition, hardness of compound coatings increased as soli d fat content (SFC) at 25 degrees C of binary mixtures increased. Also , as SFC at 25 degrees C of the binary mixtures increased, induction t ime for bloom formation and time to fully bloom for compound coatings decreased. Observation of eutectic behavior for binary mixtures indica ted softness in a compound coating with the same fat composition, but the converse was not necessarily true.