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The sugar cane contains about 18 per cent of sugar. The canes are crushed and passed through powerful presses. The juice is boiled in vacuum pans with a little milk of lime, added to neutralize the acids which the juice contains; this forms a scum, which is taken off. After the boiling has concentrated the juice sufficiently, it is run into a large vessel to crystallize.

The mass of crystals formed is drained from the syrup, and is known as

or muscovado sugar. The non-crystallized portion is known as molasses.

This boiling down in vacuum pans has deprived the housewife of the old-fashioned West India or New Orleans molasses, with which she made such delicious gingerbread, which even “mother” can no longer prepare. The acid molasses produced by the slow evaporation of the sugar cane juice in open pans is to be found only rarely and in small quantity on the market. In 1903–04 only 27,964,292 gallons of molasses were produced in the United States as against 37,000,000 gallons in 1902-03.

The grades of sugar also have changed very much. The dark brown sugars have almost disappeared from the market. This is owing to the improved methods of boiling. The granulated is of the same quality as loaf sugar, only the syrup is stirred while crystallizing, so that the crystals do not cohere. The light brown sugars are the next product, containing some molasses, and therefore they taste sweeter, since the flavor is more pronounced in the colored portion of the juice.

If the granulated sugar is not quite freed from the syrup, it tastes more decidedly sweet than if it is perfectly pure. That is, it has more the taste which we are accustomed to associate with sugar.

It is often said that powdered sugar must be adulterated, because it does not sweeten as much as loaf sugar; but such is not the case, and some explanation must be sought. The reason seems to be twofold: first, a spoonful of powdered sugar does not weigh as much as a spoonful of granulated; second, since sweetness is a physical property, the finely divided condition of the sugar has something to do with it. The coarser grains seem to excite in the nerves of taste a stronger vibration, so to speak, in dissolving than do the fine particles. To prove this, equal weights of loaf, of granulated of different degrees of fineness, of powdered, and of coffee-crushed sugar were dissolved in equal volumes of water and then tested by various persons, the tumblers containing the solutions being numbered, so that the taster was an unbiased judge. Some pure honey was added to the list, and the results confirmed the previous suspicions that the taste was not due to the chemical purity of the substance. In every case the coffee sugar was pronounced the sweetest, and that of the solution of honey the least sweet. As to the solutions of the other sugars, which were all pure sucrose, judgments varied, showing that the sensation of sweetness is not owing solely to the presence of a certain amount of sucrose.

That beet root contained a sugar identical with that obtained from the sugar cane was first made known by Margraf in 1747. But the beet was not cultivated for the purpose to any extent until the middle of the last century. Under the protection of Napoleon I., the industry gradually gained ground. A prize of a million francs was offered for the successful manufacture of sugar from plants of home growth. As late as 1860 the fate of beet sugar was doubtful, since the disagreeable flavor of the molasses still clung to the crystallized sugar. But applied science has overcome all the difficulties. The purest loaf sugar is now made from beets, and there is produced one and one-half times as much beet sugar as cane sugar.

The total amount of beet sugar produced in 1840 was 50,000 long tons. The total amount of cane sugar produced in 1840 was 1,100,000 long tons. The ital amount of beet sugar produced in 1905 was 6,990,000 long tons. The total amount of cane sugar produced in 1905 was 4,908,000 long tons.

The culture of the beet has spread throughout Germany and Russia. It has been tried in England, Ireland, and the Northern United States, and is proving a source of profit in many latitudes where the sugar cane will not thrive. Beets contain up to 10 or 12 per cent of sugar. In Belgium and France they extract about 7 per cent, and in Germany 8 or 9

The process of manufacture differs little from that of cane sugar.

The molasses from beet sugar is mostly sent to the distillery, as it has a very disagreeable taste.

In parts of the United States and in Canada sugar is made from the sap of the maple, Acer saccharinum, and other allied species. The sugar is cane sugar, or

per cent.

sucrose, and the accompanying substances in the sap give an agreeable flavor quite peculiar to maple sugar. Several million pounds are annually produced.

The cultivation of the Chinese sugar grass, or sugar millet (Sorghum saccharatum), has been attempted in the United States, with some success. It seems to be suited to a warm temperate zone, and thus is intermediate between the northern maple and beet and the tropical sugar cane. It is used largely for fodder, however.

The term sugar, as used today, is a very general one covering a wide range of substances, the number of which is constantly growing by virtue of chemical research.

The housewife has to do with two of the great groups :

The monosaccharids (C6H12O6), or glucoses. At least fifteen are named, to which belong grape sugar (dextrose), crystallizable; fruit sugar (levulose), non-crystallizable; and invert sugar, a mixture of the two (made from the sucroses by boiling with acid). The disaccharids (C12H2011), or sucroses.

To this class belong cane sugar, or sucrose, beet sugar, maple sugar, malt sugar (maltose), and milk sugar, or lactose.

The sugars are often divided into reducing (those which reduce copper from copper sulphate), maltose, lactose, invert sugar, dextrose, levulose; and nonreducing, as cane sugar, beet sugar, maple sugar.

Starch is a polysaccharid, along with cellulose, dextrin, glycogen, and pectin. It can be considered as

I.

2.

an aggregation of 100 groups derived from dextrose, C&H 206 (100 C6H1003), by the removal of water from each during plant growth. These water molecules may be replaced and sugar again formed by treating with acid (artificial or unnatural) or by the action of an enzyme, as diastase, the natural ferment found in barley in abundance.

In the acid hydrolysis the starch breaks up gradually into maltose, a dextrin, and dextrose. In the enzyme treatment only the first two result as a rule.

Much confusion is caused by the loose way in which the term “glucose” is commonly used. Formerly it was the designation of all the manufactured products, whether solid or viscous, but of late the term “starch sugar,” or dextrose, covers the solid sugars and glucose means the syrup form, from the Greek glukus, meaning sweet.

While all kinds of starch, and even cellulose, will yield starch sugar when treated (hydrolyzed) with acid, corn is the chief source. The grain is soaked in huge vats, holding some 2,500 bushels, in warm water for several days.

Sulphur dioxide is added to sterilize and to soften the hulls. The grain is then ground, and the starch is washed through bolting cloth sieves and allowed to settle. If it is desired to save the germ, a first coarse grinding allows it to float away and a second finer grinding sets free the starch grains.

The collected starch, mixed with water to a creamy consistency, is run into copper boilers with about six pounds of hydrochloric acid to each 10,000 pounds of starch. It is heated under pressure of some thirty

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