Shallenberger, R.S., Acree, T.E. and Guild, W.E. 1965.
Configuration, Conformation, and Sweetness of Hexose Anomers.
J. Food Sci. 30(3): 560-563.
There are two general problem areas concerning the sweetness, configuration, and conformation of hexose anomers which are important in the field of flavor chemistry. First an uncertainty exists as to whether a-or B-D-glucose is sweeter. Second, the original work of Boeseken (1949) has been criticized. Anomers of the common hexoses in question were secured or prepared. The studies of Boeseken were repeated with conventional laboratory, conductance equipment, and taste tests were conducted on the cystalline sugars. The sweeter sugar anomers in the crystalline form, with fixed conformations, are those that react less strongly with boric acid. Those which react more strongly with boric acid are less sweet. B-D-glucose when dissolved in boric acid solution, does not initially increase the conductivity of the solution if corrections are made for the sugar and the boric acid alone. As mutarotaion proceeds the changing conductance parallels and correlates the formation of the a-anomer. a-D-glucose increases the conductance of boric acid solutions immediately upon dissolution, but with the formation of the B-anomer, conductance gradually decreases. In light of the deductions made from conductivity and conformational studies, these is no need to consider altering the presently accepted configurational assignment for a-D- and B-D-glucose.