from The American Heritage® Dictionary of the English Language, 4th Edition
- n. See fructose.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. D-fructose, the left-rotating stereoisomer of fructose
from the GNU version of the Collaborative International Dictionary of English
- n. A sirupy variety of sugar, rarely obtained crystallized, occurring widely in honey, ripe fruits, etc., and hence called also fruit sugar; also called fructose. Chemical formula: C6H12O6. It is called levulose, because it rotates the plane of polarization of light to the left, in contrast to
dextrose, the other product of the hydrolysis of sucrose.
from The Century Dictionary and Cyclopedia
- n. A sugar (C6H12O6) isomeric with dextrose, but distinguished from it by turning the plane of polarization to the left.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a simple sugar found in honey and in many ripe fruits
Fructose Fructose, also called levulose, has exactly the same chemical formula as glucose, but the atoms are arranged in a different structure.
The sugar is not all like the common granulated sugar, but in ripe fruits a part is in the form known as levulose or fruit sugar, which is two and a half times sweeter than granulated sugar.
The total sugar content in processed foods is often unclear from the ingredients list, where different sugars can be listed separately as sucrose, dextrose, levulose, fructose, corn syrup, high-fructose corn syrup, etc.
Unquestionably it could have used some form of sugar; perhaps dextrose, such as Thrykar himself could digest — perhaps levulose or fructose or even starch.
The cane sugar, however, does not ferment directly: the enzyme in the yeast first transforms the sugar into dextrose and levulose, and these sugars then undergo alcoholic fermentation.
When a solution of cane sugar is heated with hydrochloric or other dilute mineral acid, two compounds, dextrose and levulose, are formed in accordance with the following equation:
If we now streak these plates with an organism, _e. g._ a yeast, which saccharifies starch, it is possible to tell whether maltose or levulose and fructose are formed; if the former, only those plates containing _P. phosphorescens_ will become luminous; if the latter, only those containing _P.
The author maintains that unsatisfactory results are obtained in determinations of starch when the method employed is based upon the inversion of sugar, formed as an intermediate product, since maltose, dextrose, and levulose are partly decomposed by boiling with dilute acids.
The change that is brought about in the sugar by the cooking of fruits consists in changing the cane sugar into levulose and dextrose, which are not so sweet.
It is also noteworthy that levulose gave this same product, the trinitrate of the anhydride (levulosan) by both methods of nitration (_supra_).