Page:Foods and their adulteration; origin, manufacture, and composition of food products; description of common adulterations, food standards, and national food laws and regulations (IA foodstheiradulte02wile).pdf/511

takes place at the final moment of evaporation and usually the whole mass is sold as sugar, forming what is known in the cane sugar industry as concrete. Maple sugar is never refined, since in the process of refining the peculiar flavor and odor which give it its chief value would disappear. The quantity of maple sugar made in the United States is almost negligible from a commercial point of view, amounting annually to only about 10,000 tons. Perhaps a greater quantity of maple sap is used in the form of sirup than of sugar.

Fig. 79.—Boiling the Maple Sap.—(Courtesy Forest Service, Department of Agriculture.)

Refining of Sugar.—All kinds of raw sugar but maple are refined before entering commerce. The public taste has demanded a pure white sugar and in so far as beet sugar is concerned the refining process is a necessity, inasmuch as raw beet sugar has a very disagreeable soapy taste and odor which render it unfit for consumption. On the other hand raw cane sugar is aromatic, fragrant, and delicious to a far greater degree in the raw state than when it is refined, since after the refining process it is difficult to distinguish the product of the beet juice from that of the sugar cane.

Process of Refining.—The manipulation attending the refining of sugar is a somewhat simple one, but experience has shown that it can only be done economically in very large establishments, many of which cost millions of dollars. The attempt to refine sugar on a small scale makes the product too expensive to compete commercially with the product of the large refinery. The raw sugar is first mixed with water and melted and reduced to the condition of a sirup. In this state it is treated with lime and clarified as has