The Story -Book of the Fields 



sugar by the heat, and the tuber has become 

 a sweet, floury paste. The same thing applies 

 to the chestnut. When raw it is not good 

 for much, although it is sometimes eaten ; 

 but when baked it deserves all praise and is 

 another instance of the conversion of starch 

 into sugar by means of heat. Beans and peas, 

 as hard as bullets when dry and without any 

 pleasant taste, are distinctly sweet as soon as the 

 boiling water has affected their starch. And 

 all our floury foods undergo the same change. 



In order to convert starch into sugar, 

 industry makes use of a more powerful means 

 than heat alone. It is boiled in water, with 

 the addition of a small quantity of sulphuric 

 acid or oil of vitriol, and under the influence 

 of this powerful liquid the starch becomes a 

 sweet syrup. Of course, as soon as it is 

 formed the syrup is purified from the oil of 

 vitriol which has helped to produce it. 



The sugar obtained in this way is a soft, 

 sticky substance, almost as sweet as hone3< T , 

 but very different from ordinary sugar. It 

 is called glucose, and confectioners make 

 great use of it. When we eat a sugar-plum, 

 it is generally starch and glucose. Many of 

 the pastrycook's or confectioner's dainties, 

 which seem to be sweetened with ordinary 



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