Crystallization is a term that describes several different phenomenon related to the formation of a crystalline lattice structure.
Crystallization is often a four step process that includes:
*Generation of a supersaturated state
*Nucleation – formation of nuclei
*Propagation – crystal growth
*Maturation – crystal perfection or continued growth
The liquid phase remaining after the formation of the crystals is called ‘mother liquor’.
In the food industry, crystallization may serve for the recovery of crystalline products – (sugar, glucose, lactose, citric acid, salt), for the removal of certain undesirable components or for modification of certain food products in order to obtain a desirable structure.
Several materials may also crystallize during food processing.
Crystallization of triglycerides
Crystallization of triglycerides is a complex phenomenon characterized by fairly slow growth rates and polymorphic transitions of their crystallized phases.The crystallization of triglycerides is also complicated by the presence of minor components frequently contained in them. For examples, milk fat consists of 95-98% triglycerides but also contained diglycerides, free fatty acids, monoglyceride, phospholipids and sterols as minor components.
Crystallization of sucrose
Crystallization is the final step in the recovery of sugar from sugar cane or sugar beet. Also called ‘sugar boiling’, sugar crystallization of sugar is a complex process requiring precise control, skill and experience.
Crystallization process is used as a unit operation for separation of solids from the liquids or as a process tool for processing certain foods item.
In the separation process, in some cases the solids are the desired products, whereas in others liquid is the desired product.
Crystallization in foods
