Nature and composition of fat bloom from palm kernel stearin and hydrogenated palm kernel stearin compound chocolates

Palm kernel stearin and hydrogenated palm kernel stearin can be used to prepare compound chocolate bars or coatings. The objective of this study was to characterize the chemical composition, polymorphism, and melting behavior of the bloom that develops on bars of compound chocolate prepared using these fats. Bars were stored for 1 year at 15, 20, or 25degreesC. At 15 and 20degreesC the bloom was enriched in cocoa butter triacylglycerols, with respect to the main fat phase, whereas at 25degreesC the enrichment was with palm kernel triacylglycerols. The bloom consisted principally of solid fat and was sharper melting than was the fat in the chocolate. Polymorphic transitions from the initial phase to the phase accompanied the formation of bloom at all temperatures.