The study of triacylglycerol interactions in the solid phase and their behaviour during crystallisation requires the availability of individual triacylglycerols of proven positional and structural purity. The aim of this work was to prepare some specific triacylglycerols and to examine their crystallisation behaviour as individual samples and in binary mixtures with each other. The first part of this thesis details the synthesis of glycerol 1-stearate 2-caprate 3-palmitate, glycerol 1-stearate 2-oleate 3-palmitate, glycerol 1-stearate 2-elaidate 3-palmitate, glycerol 1-stearate 2,3-dimyristate and glycerol 1,3-dipalmitate 2-laurate. The unsaturated acids used were isolated from olive oil and modified where required. Methods of analysis for quantitative purity determination are given. The second part of the thesis involves the examination of the selected triacylglycerols by methods of X-ray powder diffraction and differential scanning calorimetry. The triacylglycerols prepared as described were supplemented by lipid samples from other sources [glycerol 1-stearate 2-laurate 3-myristate, glycerol 1-stearate 2-myristate 3-laurate, glycerol 1-palmitate 2-stearate 3-oleate, glycerol 1-palmitate 2,3-dielaidate, glycerol 1,2,3-triarachidate, glycerol 1,2,3-triplamitate, glycerol 1, 2,3-tristearate and cocoa butter]. The polymorphic forms of samples prepared from solvent and from thermal conditioning were obtained. Five pairs of the triacylglycerols were chosen for examination as binary mixtures. The preparation methods and result detailed and summarised in temperature vs. composition (phase) diagrams.