Reducing sugars composition

Composition. Molasses composition depends on several factors, eg, locality, variety, sod, climate, and processing. Cane molasses is generally at pH 5.5—6.5 and contains 30—40 wt % sucrose and 15—20 wt % reducing sugars. Beet molasses is ca 7.5—8.6 pH, and contains ca 50—60 wt % sucrose, a trace of reducing sugars, and 0.5—2.0 wt % raffinose. Cane molasses contains less ash, less nitrogenous material, but considerably more vitamins than beet molasses. Composition of selected molasses products is Hsted in Table 7. Procedures for molasses analysis are avadable (59). 

Hultiple products are frequently observed for the separation of TMS-sugar derivatives. At equilibrium reducing sugars can exist in more than one isomeric form known as anomers. Formation of their THS derivatives followed by gas chromatography will result in multiple peaks corresponding in composition to the equilibriue anomeric mixture [436]. 

The popular, but erroneous, concept of an aqueous solution of a reducing sugar is of one containing large, and comparable, proportions of the two pyranoses, and only small proportions of the furanoses, but the composition may, in fact, vary within wide limits. At one extreme (for example, glucose), the furanoses can be barely detected, and, at the... 

The composition of solutions of the 2-heptuloses has been determined, and discussed, by Angyal and Tran.92 These ketoses are different from other reducing sugars inasmuch as there are two hydroxymethyl side chains attached to the pyranose ring. In the a-pyranose form, they are cis to each other and will therefore both be equatorial in the preponderant chair form. In the / -pyranose, however, one or other of the hydroxymethyl groups has to be axial and, in consequence, the / anomers are disfavored in only one solution (that of the altro isomer) was the yS-pyra-nose detected in the 13C-n.m.r. spectrum.92... 

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