Melt crystallization benefits

Melt Crystallization. Crystallization (qv) from a melt is inherently more attractive than distillation because the heat of fusion is much lower than that of evaporation. It also benefits from lower operating temperature. In addition, organic crystals are virtually insoluble in each other so that a pure product is possible in a one-stage operation. 

Very impure compounds typically do not crystallize well. Additionally, the target compound can oil out of solution if the solution reaches saturation above the melting point. Crystallizations for purification should be stirred. Crystallizations benefit by seeding with crystalline material therefore, it may be beneficial to purify a small amount of material by column chromatography to determine the melting point, and to have seeds before proceeding with a crystallization. 

Interesterification. The least known and practiced processing technique available to the fats and oUs processor for modification of the physical properties of an oil is interesterification, often referred to as rearrangement. The ability to modify the melting point and functional crystallization characteristics without changing the fatty acid composition makes interesterification a process with a number of unique possibilities. The benefits of the random interesterification processes are summarized in Table 21 (133). 

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