Selective anomer crystallization from aqueous solution: Monitoring lactose recovery under mutarotation limitation via ATR-FTIR and theoretical rate analysis

Lactose is typically produced via cooling crystallization either from whey(-permeate) (edible-grade) or aqueous solution (pharmaceutical-grade). While in solution, lactose present 2 anomeric forms, α- and β-lactose. During under standard process conditions, only α-lactose crystallizes, depleting the of α-anomer. In practice, mutarotation kinetics are often assumed to be much faster than crystallization. However, some literature reports limitation by mutarotation. research, we investigate influence operating conditions on explore existence an operation regimen where can disregarded process. Therefore, study solutions inline monitoring concentrations β-lactose attenuated total reflection Fourier-transform spectroscopy (ATR-FTIR). By implementing a linear profile 9 K/h minimum temperature 10°C, measured remarkable increase β/α-ratio, reaching maximum 2.19. This ratio exceeds equilibrium level 36%. when same was applied 25°C, deviation significantly lower, with β/α-ratio 1.72, representing 8% equilibrium.We also performed theoretical assessment parameters kinetics. We conclude that needs taken into consideration for efficient control if crystal surface area supersaturation sufficiently high.