ALTERATION IN THE RATIO OF α‐ TO β‐LACTOSE CO‐CRYSTALLIZED FROM ORGANIC SOLVENTS

Crystallization of lactose from alcohols and mixtures with dimethyl sulfoxide (DMSO) was studied. The effect of solvents, moisture, pH and temperature on the mutarotation equilibrium of lactose also was investigated. Equilibrium was attained in supersaturated alcoholic solutions in a reasonable period of time when solutions were prepared at refluxing temperatures or where acid or basic medium was present. Quantitative measurement of the anomers produced by these treatments was by GLC. The α/β ratio in the crystals obtained from the solutions in most cases approximated 3α-lactose/2βlactose which was shown by infrared spectra to be equivalent to a simple mixture of the two anomers.