837 



FOOD. 



FOOD. 



858 



contain other alimentary principles besides sugar, which assist in the 

 nutrition of the body. 



Sugar, being readily soluble in water, is more digestible than starch. 

 Of the substances which maintain animal heat, it is the most easily 

 digested ; and hence we may see a reason why it is supplied to the 

 young of the higher forms of animals. For this purpose it is secreted, 

 by the female of all the Mammalia, in the milk, which is furnished 

 universally to their young during the first months of their existence. 

 The instinctive love of sugar, so well known as a distinguishing character 

 of the child, seems to point out its adaptation to the wants of the 

 infant system. Readily digestible however as sugar is, it is one of 

 those substances which speedily undergoes decomposition. When 

 taken into the stomach and the system, its elements seem to enter 

 into secondary combinations, which are very injurious. This is why 

 so many persons find it necessary to limit the quantity of sugar which 

 they take in their diet. The changes however which it so frequently 

 undergoes in the adult system, do not appear to take place hi children ; 

 hence the child may eat sugar with impunity, although its parents 

 may not 



Although there are various kinds of sugar, having a different com- 

 position, they seem all to act dietetically in the same way upon the 

 system. The most common form of sugar in plants, and that which 

 is most frequently eaten in diet, is Cane-Sugar, so called from its being 

 yielded by the sugar-cane. It consists of 



Carbon 

 Hydrogen 

 Oxygen 

 Water . 



Atoms. 



. 12 



. 9 



, 9 



2 



The other kinds of sugar which are eaten, are milk-sugar, C 2 ,H 19 

 O 19 + 5HO ; and grape-sugar, C,, H,, 12 + 2HO. It will be seen that 

 cane-sugar resembles etarch in its composition, and it is probably 

 formed in the plant from that body. Although cane-sugar is found 

 in the sugar-cane, the beet, and the maple, it ia not so frequent in 

 plants as grape-sugar, which is the form in which sugar is found in 

 the fruits and other parts of plants which may be sweet. 



The sources of sugar, as an article of diet, are of course very 

 various; it is only separated however from a limited number of 

 plants. Of these the principal ig the sugar-cane (Sacc/tarum 

 officinarum). 



The sugar eaten by the inhabitants of France is principally 

 obtained from the Beet (Beta vulgarit). In tropical countries it is 

 obtained from the juice of palms, as from the Jaggary Palm 

 (Caryota urnu), the Cocoa-Nut Palm (Cocot nudfera), and others. 

 It exists in the stems of all grasses, and is prepared in America from 

 Maize (Zea ifayi). The Birch (Betula alba) in this country, and the 

 Sugar-Maple in America (Acer taccharinum), also yield it in their sap. 



Grape-sugar, also called Glucose, is found in the fruits of most 

 plants. It seems to act on the system in precisely the same way as 

 cane-sugar. 



The result of the fermentation of grape-sugar is the production of 

 Alcohol, which does not difer much in composition from sugar. 

 The following is the decomposition : 



C. II. O. 



2 Atoms of Alcohol . . . . 8 12 4 

 4 Atoms of Carbonic Acid . . . 408 

 2 Atoms of Water 022 



One Atom of Grape-Sugar . . 12 14 14 



Alcohol is taken as an article of diet in the form of beers, wines, 

 and spirits. Although resembling sugar in its composition, its effects 

 on the system are very different. It acts on the nervous system as 

 a stimulant and narcotic, and might perhaps be regarded as one of 

 the medicinal forms of food. A question has arisen amongst 

 physiologists as to the action of this substance on the system. Liebig, 

 and with him many others, maintain that like starch and sugar 

 and oil, the elements of the alcohol unite with oxygen in the system, 

 and thus by combustion assist in maintaining animal heat. On the 

 other hand Dr. Carpenter, and those who repudiate the use of alcohol 

 in diet, maintain that it is not destroyed during respiration, and 

 consequently does not promote animal heat any further than as it 

 stimulate* the heart's action. 



Alcohol when taken as an article of diet not only acts upon the 

 nervous system, but on account of its chemical action on albumen 

 exert*! an injurious influence when taken in large quantities upon the 

 mucous membrane of the stomach. It is thus that when indulged 

 in, it becomes a source of indigestion, and lays the foundation of 

 serious diseases. Taken in small quantities in the form of wine or 

 beer, it seems to exert a favourable influence on the digestive function, 

 and to belong to that class of foods to which spices and condiments 

 are referred. Taken medicinally it is often capable of exerting 

 powerful effects, on account of its rousing action upon the vascular 

 system. It does not seem to be necessary to health, as there are 

 many nations that never use it, and individuals, in countries where 

 it is habitually taken as an article of diet, find their health not 

 materially injured by debarring themselves from its use. 



The quantity of alcohol contained in fermented beverages varies 

 very much. 



With regard to wines, when the juice of the grape contains large 

 quantities of sugar in comparison with the water, and the fermen- 

 tation is complete, then the alcohol is abundant, and strong wines 

 are produced ; whilst, when the sugar is iu small quantities, or the 

 fermentation is incomplete, weak or thin wines are the result. Ports 

 and sherries are strong wines, whilst those of the Rhine are generally 

 weak. 



Sweet wines are those in which all the sugar is not converted into 

 alcohol. This is mostly the case with wines made from other fruits 

 besides grapes. Hence the well-known sweetness of what are called 

 British wines. This does not however arise from an imperfect fer- 

 mentation, but from the acid contained in other fruits not being 

 tartaric acid. One of the most remarkable properties of tartaric acid 

 is that it forms an insoluble salt (the cream of tartar) with potash, 

 which is generally found in fruits ; and in wines made from the grape 

 this salt falls to the bottom of the cask, forming the tartar or lees of 

 the wine. But other acids, as citric, malic, and oxalic acids, are not 

 thus precipitated from their solutions, and they remain in wines, 

 giving them a very acid flavour, which would render them unpleasant, 

 unless sugar was added to cover their acidity. Sweet wines are 

 objectionable as articles of diet, on account of the sugar they 

 contain, which, when held in solution in wine, seems more likely to 

 decompose, and thus prove injurious to the system, than when taken 

 in its pure form. In wines made from other fruits besides grapes, 

 the acid is also liable to objection. 



Effervescing wines are those which are bottled before the fermen- 

 tation is complete, so that a large quantity of the carbonic acid, which 

 would be otherwise got rid of, is retained in solution in the wine, and 

 escapes when the bottle is uncorked. Such is champagne. Effer- 

 vescing wines are more liable to disagree with delicate stomachs than 

 others, on account of their imperfect fermentation rendering them 

 liable to further change in the stomach ; and this state of change is 

 probably communicated to the substances used as food contained in 

 the stomach. 



The skins and stalks of the grapes, if not the juice, contain tannin. 

 This substance is a powerful astringent, and its presence seems to be 

 the cause of the astringent character of many red wines, as port, 

 claret, and others. There is slso a difference in the quantity of free 

 tartaric acid contained in wines ; and those which have the largest 

 proportion of this constituent have an acid flavour. Some of the 

 wines made from grapes are so sour as to be very unpalatable : this 

 is more especially the case with the poorer white wines of the Rhine. 



The quality iu which wines differ from each other most is what is 

 called their bouquet, or flavour. It differs in wines made from 

 different kinds of grapes, and differs in the same grape in different 

 districts and in different seasons. It is well known that the vintage 

 of one year produces a better or worse wine than that of another, and 

 this depends on the development of the peculiar flavour of the wine. 

 Liebig says that the bouquet is dependent on an acid which he calls 

 ccnanthic, and which, combining with the alcohol, forms an ether 

 which gives the odour and flavour to wines. 



The quantity of alcohol contained in wines differs very much. The 

 ports and sherries consumed in England contain the largest quantity. 

 But then much of this is added. It is added in the form of brandy. 

 Brandied wines keep best, but are not the best to drink. Unless 

 wines are naturally strong, they will not keep without the addition of 

 alcohol. Clarets, hocks, and Moselles, are seldom brandied. Some 

 of the hocks do -not contain more than seven per cent, of alcohol, 

 whilst port and sherry contain twenty-five per cent. 



Ardent spirits, distilled liquors, differ from wine in their having 

 been submitted to distillation after the fermentation, which produces 

 the alcohol. Brandy is distilled from wine; and peach-kernels, or 

 other vegetable matter containing oil of bitter almonds, are added to 

 give it a flavour. All the parts of the plants belonging to the division 

 of the order Rosace(s, called Amygdalece, contain oil of bitter almonds. 

 Rum is distilled from molasses or treacle in the West India Islands, 

 and pine-apples are added to give a peculiar flavour. Gin is distilled 

 in Holland, from rye; in this country from wheat, the grains of which 

 are allowed to become saccharine, and then fermented. Juniper 

 berries are employed to give the peculiar flavour to gin. Whiskey is 

 distilled from wheat, barley, or oats, treated in the same manner as 

 for gin. Nothing is added to flavour it; but the smoke of the peat, 

 by the aid of which the distillation is effected in both Ireland and 

 Scotland, gives a characteristic flavour to this liquor. Liqueurs 

 belong to this division; they are distilled spirits containing large 

 quantities of sugar, and are flavoured with all kinds of substances, as 

 celery, bitter almonds, gentian, wormwood, &c. 



Beers, Ales, and Porters, differ from wines in the addition of a 

 bitter principle, most frequently the hop, to the fermented liquor. 

 The saccharine matter for fermentation is obtained through barley. 

 The grain of barley is steeped in water, and allowed to germinate. 

 When the starch of the grain is converted into sugar, it is submitted 

 to heat, and malt is formed. The malt is placed in boiling water, 

 and hops added ; when cooled, the process of fermentation is allowed 

 to take place, and the beer is completed. When the malt is slightly 

 charred during the process of drying, it gives a dark colour to the 



