1474 The Cornell Reading-Courses 



Use of acids and glucose in sugar cookery 



If a cane sugar solution is cooked with an acid, such as lemon juice, 

 cream of tartar, sour milk, or vinegar, the cane sugar is gradually changed 

 to glucose and fructose. If there is a sufficient amount of acid or if the 

 cooking is continued for a sufficiently long time, all the cane sugar will 

 be changed to glucose and fructose. Glucose is only about three fifths 

 as sweet as cane sugar, and, as has been said before, it is very difficult 

 to crystallize glucose and the crystals that form are very fine. Its presence 

 in a cane sugar solution, therefore, modifies the type of crystallization that 

 takes place when the solution is cooked, and decreases the sweetness of 

 the solution. Acids are used in making candy and in making frosting 

 because of their effect in producing glucose. Very small quantities of 

 acids are used because there is a limit to the amount of glucose desired 

 and because they affect the flavor of the mixture. If too much glucose is 

 produced in a sugar solution, a sticky mixture results instead of a creamy 

 one. Instead of cooking a cane sugar solution with acid in order to 

 produce glucose, glucose may be purchased as such and may be added 

 directly to the sugar mixture. This is the common practice in making 

 candy on a large scale. Acid impurities in some grades of sugar cause 

 the change from cane sugar to glucose. In making candy and frosting 

 from brown sugar no acid need be added, since the sugar contains sufficient 

 acid impurities to aid in producing glucose. 



Effects of premature formation of crystals in a sugar solution 



If crystals are allowed to collect on the sides of the pan while a cane 

 sugar solution is cooking, they may cause a coarse recrystallization of the 

 mass. These crystals, therefore, should be kept washed down with a 

 wet cloth or a small wet brush. If the pan in which the sugar solution 

 is cooking is covered for the first part of the cooking period (about five 

 minutes) , sugar crystals are not likely to form in any quantity on the sides 

 of the pan. The steam formed by the boiling of the solution will dissolve 

 any such crystals. 



Method of reducing an overcooked sugar solution 



Success in sugar cookery depends on the ability of a person to cook a 

 sugar solution to the proper degree of concentration for the use that is 

 to be made of it. vSometimes in cooking a sugar solution for frosting 

 cake it becomes overcooked, or, in other words, it becomes too concen- 

 trated. If the sugar mixture has not reached the caramel stage, it is a 

 simple process to reduce the amount of concentration by adding more 



