A. Class Experiment.
Boil1/2 c. sugar in 1/4 c. water. Test by dropping product into cold water at the following stages. Feel the ball in 2, 3, 4, and 5. Note color in last.
1. 233 degrees Fahrenheit - "Hair" or "Thread" stage.
2. 236-242 degrees Fahrenheit - Soft ball stage.
3. 254 degrees Fahrenheit - Hard stage.
4. 260-275 degrees Fahrenheit - Crack stage.
5. 290-350 degrees Fahrenheit - Caramel stage.
6. 290 degrees Fahrenheit - Hard crack stage.
Syrup at the thread stage is used in making frosting.
Prepare peanut brittle by pouring the syrup at caramel stage over chopped nuts spread on a buttered pan. Mark in squares as it cools.
B. Class Experiment. Crystallization of Sugars.
Dissolve 2/3 c. sugar in J c. water. Divide into 3 portions.
1. Boil first portion to hard crack stage, and set aside to cool.
2. To the second portion add 1/2 tsp. vinegar or lemon juice or a pinch of cream of tartar. Boil to hard crack stage and set aside to cool.
3. To the third portion add one-fourth the volume of glucose. Boil to hard crack stage and set aside to cool.
Why is acid or glucose added in making many candies?
Make such candies as time and circumstances warrant. Cook to:
1. Soft ball stage (238°) Panochi, Fudge (Chocolate cream candy), Cocoanut Cream Candy, Fondant.
2. Hard ball stage (254°) Chocolate Caramels, Plantation Drops, Butter Cups.
3. Crack stage (270°) Molasses Candy, Ice Cream Candy, Vinegar Candy, Popcorn Balls, Butterscotch.
4. Hard crack stage (290°) Glace-Fruit, and Nuts. For recipes see cook-books.
The carbohydrates are divided into three groups according to their complexity, and are called mono-, di-, and poly- saccharides. The chief members of the groups are as follows:
Composition of Foods containing Sugar.
Glucose or dextrose
Sucrose or "sugar"
Fructose or levulose
Milk sugar or lactose
Malt sugar or maltose
All the members of the first and second group are sugars, and all are soluble in water and more or less sweet in taste. The two groups are sometimes called single and double sugars. A plant probably manufactures a single sugar out of carbon dioxide and water, and then changes the single sugar into either double sugar or polysaccharides. When polysaccharides or disaccharides are digested, or boiled with water and acid, the plant-manufacturing process is reversed and the substances are finally broken down into single sugars. To prove this, chew a bit of cracker, being careful not to swallow it before the sweet taste of the sugar is evident. The breaking down process also goes on in the plant when stored starch or sugar is used for further growth, as, for example, in a potato when it sprouts.
Glucose and fructose occur in many fruits and vegetables and are present in large quantities in honey. Glucose is used so extensively for food that it is also manufactured from cornstarch by boiling the starch with acid. The chief points to be remembered about these two sugars are that they do not need to undergo any process of digestion before being absorbed, that they do not crystallize so readily as cane sugar, and that they give the sugar test. Galactose is a digestive product of milk sugar and is not found as such in foods.
Of the disaccharides, sucrose and lactose are the more important in our foods. Lactose is found in milk. It ferments in the stomach less readily than sucrose and so is probably much better for babies. Accordingly, modified milk and other baby foods are often prepared by the addition of lactose. It is also used as a basis for sugar pills. It is manufactured commercially by separating it from milk. When sucrose is boiled with an acid in the presence of water it changes into equal parts of glucose and fructose. Glucose is far less sweet than sucrose, but fructose is much sweeter. Consequently the mixture, "invert" sugar as it is called, is not very different in sweetness from the original sucrose, but the latter is probably a little sweeter. Some recipes call for the addition of sugar to acid fruits after boiling, so that this change will not take place as a result of the cooking. The saving is probably so small as not to be appreciable. On the other hand, this change is deliberately sought after in making candies like fondant and fudge which must be smooth and velvety, not granular, and in candies like butter-scotch which must not "sugar."
The single sugars crystallize with much more difficulty than sucrose, and the presence of even small amounts of them makes the candy less liable to "grain" or "sugar." Sometimes, instead of bringing about the change by boiling with acid, a little glucose syrup is added to produce the same result.
During digestion all the carbohydrates are broken down into single sugars and are then absorbed and carried to the liver. Here and in the muscles any sugar in excess of that needed in the blood is stored as glycogen, or animal starch. At need, the process is reversed, the stored glycogen is again broken down into sugar to keep the supply of it constant in the blood.
Saccharin is a chemical substance with a sweet taste and is entirely unlike the carbohydrates. It has no food value, and as, in too large amounts, it interferes with digestion, its use in food sold in interstate commerce has been forbidden by the United States government.
U. S. Dept. of Agriculture. Farmers' Bulletin No. 93, "Sugar as Food", or Farmers' Bulletin No. 535, "Sugar and its Value as Food."
1. Compare sugar and starch in appearance, in taste, in their behavior in cold and hot water, and in their tendency to crystallize.
2. Compare the cost of a pound of cornstarch, of flour, of sugar.
3. What other reasons besides the economic one can you give why it would be unwise to omit all starch from our diet and replace it with sugar?
4. What are brown sugar, molasses, powdered sugar, lump sugar?
5. Why can candy with brown sugar, molasses, or glucose, be easily made with the addition of acids?
6. Grind some granulated sugar in a mortar and taste it. If powdered sugar tastes less sweet than granulated, is this a proof that it is adulterated?
7. If sugar were adulterated with either sand or starch, how would these manifest themselves?
8. What different kinds of "lump" sugar are there and what is the difference between them?
9. Which costs most by the pound, granulated or lump sugar? Why do many people consider it less expensive to serve lump sugar on the table?
10. Where is sugar produced? Do we export or import sugar? Do we use more cane or beet sugar?
11. How is glucose manufactured? Is it healthful? Why has there been a prejudice against it?