RESTRUCTURING BUTTERFAT THROUGH BLENDING AND CHEMICAL INTERESTERIFICATION .1. MELTING BEHAVIOR AND TRIACYLGLYCEROL MODIFICATIONS

Chemical interesterification of butterfat-canola oil blends, ranging f rom 100% butterfat to 100% canola oil in 10% increments, decreased sol id fat content (SFC) of all blends in a nonlinear fashion in the tempe rature range of 5 to 40 degrees C except for butterfat and the 90:10 b utterfat/canola oil blend, whose SFC increased between 20 and 40 degre es C. The sharp melting associated with butterfat at 15-20 degrees C d isappeared upon interesterification. Heats of fusion for butterfat to the 60:40 butterfat/canola oil blend decreased from 75 to 60 J/g. Blen ds with >50% canola oil displayed a much sharper drop in enthalpy. Hea ts of fusion were 30-50% lower on average for interesterified blends t han for their noninteresterified counterparts. Both noninteresterified and interesterified blends deviated substantially from ideal solubili ty, with greater deviation as the proportion of canola oil increased. The change in the entropy of melting was consistently higher for nonin teresterified blends than for interesterified blends. Chemical interes terification generated statistically significant differences for all t riacylglycerol carbon species (C) from C-30 to C-56, except for C-42, and in SFC at most temperatures for all blends.