. The chemistry of agriculture, for students and farmers. Agricultural chemistry. CARBOHYDRATES 59 hydrulyzes to equal parts of dextrose and levulose.^ This is the way it changes naturally in ])lants. Artificially, sucrose can be hydrolyzed by boiling with a dilute mineral acid like hydrochloric, the products of this acid hydrolysis being the same as with invertase. The mixture of levulose and dextrose thus produced is known as invert sugar, because the levorotatory power of levulose is greater than the dextro- rotatory power of dextrose, the net result being levorotation. The specific rotatio
. The chemistry of agriculture, for students and farmers. Agricultural chemistry. CARBOHYDRATES 59 hydrulyzes to equal parts of dextrose and levulose.^ This is the way it changes naturally in ])lants. Artificially, sucrose can be hydrolyzed by boiling with a dilute mineral acid like hydrochloric, the products of this acid hydrolysis being the same as with invertase. The mixture of levulose and dextrose thus produced is known as invert sugar, because the levorotatory power of levulose is greater than the dextro- rotatory power of dextrose, the net result being levorotation. The specific rotation of invert sugar is —20°.^ Fungi and bacteria containing invertase change sucrose to dextrose and levulose, and can then ferment to the usual products of alcohol, carbon dioxide, etc. It is not directly fermentable in most cases. 1 The hydrolytic change of sucrose into equal parts of levulose and dex- trose is shown best by the graphic formula, and illustrates very well the glucoside-like character of the sucrose molecule. (See footnote on page 53.) In fact it may be considered a "levulo-glucoside," or ";. H I H—C—O—H -H H—C—O—H H—C—O- I H I H—O—C—H I H—O—C—H H—O—C—H = H—C O—H + H—O—C—H I I H—C—O—H H—O—C—H I I H—C=0 0=C H—O- H -C- I H Sucrose. Dextrose. Levulose. The hydrogen and oxygen of water enter the sucrose molecule as indi- cated by the heavy letters, and the molecules of dextrose and levulose result. 2 The specific rotation of levulose is — ° and of dextrose is + 5: but that of invert sugar is not — 40°, but — 20°, since specific rotation is the angular rotation of a column 10 centimeters long which contains 1 gram of substance in 1 cubic centimeter (footnote p. 52), and 1 gram of invert sugar consists of | gram of dextrose and § gram of levulose, thus giving only ^ the angular difference between the specific rotations of levulose and Please note that the
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