26 T H E C U B A R E V I E W 



SUGAR AND ITS VALUE AS FOOD 



By Mary Hinman Abel, from "Farmers' Bulletin 535," U.S. Devi, of AgricuUurv. 



INTRODUCTION 



The pleasant flavor of sugar, together with what is now known of its nutritive value, 

 will account for its great popularity as a food. It may almost be said that people eat as much 

 ■sugar as they can get, and that the consumption of sugar in different countries is in general 

 proportional to their wealth. 



The English-speaking people are the largest consumers of sugar. In 1910 England 

 consumed 86.3 pounds per capita and the United States 81.6 pounds, although still larger 

 amounts are said to be consumed in sugar-growing districts, largely in the form of the ripe 

 cane. Denmark that year consumed 77.7 pounds per capita; Switzerland, 64.3 pounds; and 

 Germany, France, and Holland each about 40 pounds; while in Italy, Greece, and Servia 

 the rate was only about 7 pounds per capita. The consumption of sugar is everywhere in- 

 creasing. 



CHEMICAL COMPOSITION OF SUGARS 



The term "sugar," as here used without qualification, means the ordinary sugar of com- 

 merce, the chemical name of which is sucrose. Because this was first manufactured from sugar 

 cane it is called cane sugar, but the same sugar is manufactured from beets and is known as 

 beet sugar. It is also found in the juice of many other plants. There are other sugars which 

 are also given popular names denoting their origin — for instance, milk sugar, grape sugar, 

 and fruit sugar. The sugars may be conveniently divided chemically into several groups 

 according to the number of carbon atoms which they contain. The most important from 

 the standpoint of food value are the single sugars, grape sugar (dextrose) and fruit sugar 

 (levulose), with 6 carbon atoms; and the double sugars, cane sugar (sucrose), miUc sugar (lac- 

 tose), and maltose (malt sugar), in which the molecule contains 12 carbon atoms, or twice 

 as many as in the single sugars. (a) 



By a chemical process called inversion, which may occur in different ways, one molecule 

 of the double sugar is made to unite with water and form two molecules of single sugar. 

 In nature two single sugais, dextrose and levulose, often occur in equal proportions, and the 

 combination is then referred to as invert sugar. 



Sugar belongs to the imjiortant group oi food constituents, carbohydrates, so named 

 because as a whole they contain the element carbon in chemical combination with oxygen 

 and hydrogen, these two elements being in the same proportion as in water. Other car- 

 bohydrates closely related to sugar are starch and crude fiber, or cellulose. Sugars and starches 

 are very important foodstuffs, since with fat they supply the bulk of the energy of the diet. 

 Crude fiber, usually digested by man in limited quantities only, is, nevertheless, an important 

 foodstuff, smce it adds bulk to the diet. 



CHARACTERISTICS OF CANE SUGAR. 

 Pure cane sugar consists of a mass of white crystals (e. g., the old fashioned "rock candy") 



a The brief statement of the chemical nature and names of different sugars and other carbohydrates which 

 follows will perhaps make clear to housekeepers, as well as to others who are interested in such questions, this 

 interesting part of the chemistry of food. 



Carbohydrates are so named because they are composed of the elements, carbon, hydrogen and oxygen, the 

 hydrogen and oxygen being in the same proportions as in water, which is composed of 2 atoms of hydrogen to each 

 atom of oxygen. Though there are carbohydrates with fewer than 6 and with more than 6 carbon atoms, the prin- 

 cipal carbohydrates used as food contain 6 carbon atoms or multiples of 6. These are (1) monosaccharids (single 

 sugars), incluciing hexoses (such as dextrose, or grape sugar, and levulose, or fruit sugar), so called because the 

 molecule contains 6 atoms of carbon with 12 atoms of hydrogen and 6 atoms of oxygen; (2) disacchradis (double 

 sugars, such as cane sugar, and lactose, or milk sugar) so called because the molecule contains two of the simple 

 sugar molecules less one molecule of water, namely, 12 atoms of carbon with 22 of hydrogen and 11 of oxygen; and 

 (3) polysaccharids (such as starches) so called, because the molecule contains repeated many times the simple sugar 

 molecule minus the molecule of water or 6 atoms of carbon, with 10 of hydrogen and 5 of oxygen. When a molecule 

 of water combines chemically with a molecule of the second group, two hexose molecules are formed, and when 

 the necessary number of molecules of water combine chemically with a molecule of the third group, two or more 

 hexose molecules are formed. This process, called inversion or hydrolysis, may occur in several different ways. 



Each group of sugars contains a number of members; for example, grape sugar and fruit sugar have the same 

 chemical formula and the same percentage of carbon, hydrogen, and oxygen, although they arc not identical 

 substances. The difference in their properties is due to different groupings of the atoms. This must not be con- 

 fused with the fact that the same sort of sugar may be obtained from widely different sources. Thus grape sugar is 

 found in grapes and other fruits, and cane sugar is found in the juice of the sugar cane, beets, carrots, and other 

 plants. 



