Sugar Analysis, Ultraviolet Spectra of Sugars in Alkaline Solution

Abstract

The ultraviolet absorption spectra which are produced in alkaline solutions of some of the simple sugars have been measured. Investigation of these spectra shows that they are not due to the presence of reductone or pyruvaldehyde, as has previously been supposed. The chromogen responsible for the spectra, which was isolated by partition chromatography, is also responsible for the brown color which develops in alkaline sugar solutions. It is suggested that this chromogen is the result of condensation of compounds produced by the fragmentation of sugars in alkaline solution.

Food Colorant Identification, Isolation and Characterization of High Molecular Weight Brown Colorant of Maple Sirup

“…that maple sirup coloration developed during the sap evaporation is formed by a mechanism resembling the one proposed by Brrl and Feazel for color formation during alkaline glucose degradation ( 2 ) . This mechanism involves rapid lormation of trioses such as acetol and dihydroxyacetone from reducing sugars, polymerization of these fragments to form brcwm.…”

“…The oxygen content is loicer than the content typical of most carbohydrates, Lvhich indicates that dehydrated intermediates such as acetol have condensed to form part of the polymer. Acetol, previously identified as an important component of the steam distillate of maple sirup (20), has been postulated as an intermediate in color formation during alkaline glucose degradation ( 2 ) .…”

A facile one-pot synthesis of Cu–Cu2O concave cube hybrid architectures

“…The residual solution before adding glucose is almost completely transparent without any absorption above 250 nm, suggesting negligible Cu(II) species in the residual solution. 41 After the reaction with glucose for 3 min, the residual solution exhibited two well-resolved diagnostic peaks of glucose 42,43 around 285 and 316 nm as well as a set of weak peaks above 400 nm, indicating the remaining reductant glucose in the reaction system. As the reaction time is prolonged, the set of peaks above 400 nm became stronger, and an evident red-shift of the absorption band edge is observed.…”

TRIOSE COMPOUNDS IN MAPLE SIRUPa

“…Sattler and Zerban (26,32) have discussed the chemical fragmentation of the unfermentable reducing substances in molasses. The ultraviolet spectra of sugars in alkaline solution have been studied by Berl and Feaze1 (2), who found a close relationship among such 3-carbon carbonyls (trioses) as acetol and reductone and the color chromogen of alkaline glucose solutions. Such compounds have been isolated from milk by steam distillation by Keeney and coworkers (26).…”