DahliasBotanical Name: Dahlia Variabilis
Family: N.O. Compositae Synonym: Georgina.
The Dahlia is named after Dr. Dahl, a pupil of Linnaeus, but is also known, especially on the Continent, by the name 'Georgina.' It is a native of Mexico, where it grows in sandy meadows at an elevation of 5,000 feet above the sea, and from whence the first plants introduced to England were brought by way of Madrid, in 1789, by the Marchioness of Bute. These having been lost, others were introduced, in 1804, by Lady Holland. These, too, perished, so fresh ones were obtained from France, when the Continent was thrown open by the Peace of 1814.
Constituents: The Inulin obtained in Dandelion and Chicory is also present in Dahlia tubers under the name of Dahlin. After undergoing a special treatment, Dahlia tubers and Chicory will yield the pure Laevulose that is sometimes called Atlanta Starch or Diabetic Sugar, which is frequently prescribed for diabetic and consumptive patients, and has been given to children in cases of wasting illness.
There was a very considerable business done in this product before the War by certain German firms. In a paper read at the Second International Congress of the Sugar Industry, held at Paris in 1908, it was stated that pure Laevulose is preferably made by the inversion of Inulin with dilute acids, and that the older process of preparation from invert sugar or molasses does not yield a pure product. The first step in the technical production of Laevulose is in the preparation of Inulin, and Dahlia tubers or Chicory root, which contain 6 to 12 per cent of Inulin are the most suitable material. Chicory root can readily be obtained in quantity, and Dahlia plants, if cultivated for the purpose, should yield in a few years a plentiful supply of cheap raw material.
For extraction of the Inulin, the roots or tubers are sliced, treated with milk of lime and steamed. The juice is then expressed and clarified by subsidence and filtration, the clear liquid being run into a revolving cooler until flakes are produced. These flakes are separated by a centrifugal machine, washed and decolorized, and the thus purified product finally treated with diluted acid, and so converted into Laevulose. This solution of Laevulose is neutralized and evaporated to a syrup in a vacuum pan.
Laevulose can be produced in this manner from Chicory roots and Dahlia tubers at an enormous reduction of price from the older methods of preparing it from molasses or sugar, the resultant product being moreover of absolute purity. Its sweet and pleasant taste are likely to make it used not only for diabetic patients, but also in making confectionery and for retarding crystallization of sugar products. It can also readily be utilized in the brewing and mineral water industries.
The research staff of one of the Scottish Universities during the War developed a process of extracting a valuable and much needed drug for the Army from Dahlia tubers, and was using as much material for the purpose as could be spared by growers.