HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Twieg, W. C. Articles by Nickerson, T. A. Search for Related Content PubMed Articles by Twieg, W. C. Articles by Nickerson, T. A.

Kinetics of Lactose Crystallization

Department of Food Science and Technology, University of California, Davis

ABSTRACT

The effects of certain variables on -lactose crystallization were examined. The temperature for optimum crystallization rate varied with the initial supersaturation. Crystallization rate was not directly proportional to seed crystal surface area, probably because of false graining or because mutarotation has a limiting effect on rate as surface area is increased. When the position of the isomer balance (relative proportions of - and ß-lactose present in solution during crystallization) was studied, mutarotation rate was found to determine crystallization rate under conditions of high surfaee area. In the latter stages, however, crystallization rate itself was limiting, rather than mutarotation.

Low pH's (about pH 1) increased crystallization rate greatly as a result of increased mutarotation rate, increased rate of orientation of lactose molecules into the crystal, or both. Only in certain instances did the crystallization of lactose follow first-order diffusion kinetics. Rate of crystallization increased with some power of supersaturation greater than one.

¹ Present address: Quartermaster Corps, U.S. Army.