Determination of solid fat content (SFC) of binary fat blends and use of these data to predict SFC of selected ternary fat blends containing low-erucic rapeseed oil

Several oils and fats often used for the industrial preparation of European shortenings were blended in binary systems. The equilibrium (after 48 h at 15 degrees C) solid fat contents (SFC; determined by pulsed NMR spectroscopy) were measured and plotted against blend composition. SFC of the blends resulted from the SFC of each fat for the considered temperature as well as the type of interaction existing between those fats (namely, ideal behavior, monotectic interaction, eutectic interaction, and so on). The type of relationship fitted was dependent on the kind of interaction: Linear relationships were found for total compatibility between fats, and polynomial-type (order 2) relationships were found for fats exhibiting incompatibility. Some corresponding ternary oils and fats blends were also prepared and analyzed. Selected relationships (regression equations of the fitted curves) obtained for binary blends were combined in order to calculate the SFC of the corresponding ternary blends. Experimental values were generally close to predicted ones. The representation of SFC as a function of composition is interesting as it allows one to determine rapidly and easily the type of molecular interaction between two fats and also to determine equations that can be. combined to calculate easily the SFC of corresponding ternary blends crystallized in the same way with a good accuracy. The texture (hardness) of several binary and ternary blends was also measured. The combination of the results obtained for SFC with the results obtained for the hardness of binary blends allows the prediction of the hardness of a corresponding ternary blend under the same conditions.