CARBOHYDRATES, ACIDS, FATS, OILS 73 



The fruits generally contain saccharose, mixed with 

 other sugars and organic acids, and upon the relative 

 proportions of these compounds depends the character 

 of the fruit as to acidity or sweetness. 



98. Maltose. — ^This sugar is intimately related to the 

 first growth which occurs in the germination of seeds. It 

 stands as an intermediate product between ihe store of 

 starch in the seed and the new tissues of the sprout. The 

 solution that the brewer extracts from the malted grains 

 contains this compound as the principal ingredient, and 

 through succeeding fermentations in the beer vats it is 

 broken up into alcohol and other compounds. It sustains 

 an important relation, therefore, to the production of 

 beers and other alcoholic liquors. Glucose sirups some- 

 times contain small quantities of this sugar. It is also 

 foimd as an intermediary product in the intestinal canal 

 during the digestion of food, being derived from starch 

 and other carbohydrates through the action of ferments. 

 Maltose is similar to cane-sugar in ultimate composition, 

 but not in constitution, although as a nutrient it evidently 

 has an equivalent value. 



. 99. Lactose. — ^The only sugar of animal origin which is 

 abundant in farm life is the lactose that is found in milk, 

 which is known in commerce as milk-sugar. The milk of 

 all mammals contains sugar, which appears to be the same 

 compound with every species so far investigated. When 

 they are fed wholly from the mother, this is the only 

 carbohydrate which young mammals receive in their 

 food. The average proportion of sugar in the milk of 

 domestic animals varies from three to six parts in a hun- 

 dred, cow's milk containing about five parts. When the 

 cream is removed, much the larger part of sugar remains 

 in the skimmed milk, and in cheese-making it is nearly all 



