DYNAMIC CRYSTALLIZATION OF COCOA BUTTER .1. CHARACTERIZATION OF SIMPLE LIPIDS IN RAPID-NUCLEATING AND SLOW-NUCLEATING COCOA BUTTERS AND THEIR SEED CRYSTALS

Six cocoa butters with different crystallization induction times and t heir seed crystals were analyzed for simple lipid composition. The rap id-nucleating cocoa butter samples had higher concentrations of 1-palm itoyl-2-oleoyl-3-stearoylglycerol and 1,3-stearoyl-2-oleoylglycerol (S OS), and lower concentrations of the diunsaturated triacylglycerols, 1 -palmitoyl-2,3-oleoylglycerol and 1-stearoyl-2,3-oleoylglycerol, as we ll as higher stearic acid concentrations within their diacylglycerol f ractions when compared to the slow-nucleating samples. At the early st ages of crystallization, under agitation conditions at 26.5 degrees C, cocoa butters solidified into two fractions, high-melting and low-mel ting. The low-melting fractions were composed of polymorphs IV and V o f cocoa butter, as indicated by the onset melting temperatures of the endotherms from differential scanning calorimetry. The high-melting fr actions, which had wide melting ranges, had peak maxima of 38.5-52:2 d egrees C. Seed crystals isolated at the early stage of crystallization were characterized by high concentrations of complex lipids, saturate d triacylglycerols, saturated fatty acid-rich diacylglycerols, and mon oacylglycerols. The rapid-nucleating seed crystals had higher concentr ations of SOS when compared to their respective cocoa butters. The slo w-nucleating seed crystals did not exhibit this characteristic.