CLOSE 00 100 8 Figure 2.6 Initial solubility of x lactose and B-lactose, final solubility at equilibrium (line 1) and supersaturation by a factor 1. 6 and 2. 1(au-lactose excluding water of crystall (Modified from Walstra and Jenness, 1984.) Spontaneous crystallization can occur in the labile area without the addition of seeding material The rate of nucleation is slow at low levels of supersaturation and in highly supersaturated solutions owing to the high viscosity of the solution The stability of a lactose 'glass' is due to the low probability of nuclei forming at very high concentrations Once a sufficient number of nuclei have formed crystal growth occurs at a rate influenced by degree of supersaturation; surface area avai ilable for deposition viscosity e agitation, temperatu mutarotation, which is slow at low temperatures a-Hydrate. a- Lactose crystallizes as a monohydrate containing 5% of crystallization and can be prepared by concentrating aqueous 1a solutions to supersaturation and allowing crystallization to occur eLACTOSE 200 100 29 - 2.1 - 1 Figure 2.6 Initial solubility of a-lactose and b-lactose, final solubility at equilibrium (line l), and supersaturation by a factor 1.6 and 2.1 (r-lactose excluding water of crystallization). (Modified from Walstra and Jenness, 1984.) Spontaneous crystallization can occur in the labile area without the addition of seeding material. The rate of nucleation is slow at low levels of supersaturation and in highly supersaturated solutions owing to the high viscosity of the solution. The stability of a lactose 'glass' is due to the low probability of nuclei forming at very high concentrations. Once a sufficient number of nuclei have formed, crystal growth occurs at rate influenced by: degree of supersaturation; surface area available for deposition; viscosity ; agitation; temperature; mutarotation, which is slow at low temperatures. ?-Hydrate. cc-Lactose crystallizes as a monohydrate containing 5% water of crystallization and can be prepared by concentrating aqueous lactose solutions to supersaturation and allowing crystallization to occur below