How many will the above recipes serve?
What ingredients in these puddings scorch readily? Why is Prune Pudding surrounded with hot water during baking?
LESSON XIX
CEREALS: STARCH AND CELLULOSE
STARCH is a very important FUEL food; like sugar, it gives energy to the body. Starch is closely related to sugar; it has much the same composition and the same use in the body. In certain respects, however, starch differs from sugar.
EXPERIMENT 14: THE STARCH TEST.—Put a drop of tincture of iodine on,— corn-starch, flour, rice, cream of wheat, wheatena, oatmeal, tapioca, potato, meat, and egg. What is the result?
If a substance contains starch, it changes to a blue color when tincture of iodine is added to it.
From these experiments determine in which class—animal or vegetable—the starchy foods belong.
EXPERIMENT 15: THE EFFECT OF COLD WATER ON STARCH.—Mix half a teaspoonful of corn-starch or flour with cold water in a test tube or glass cup. What happens to a solid substance when it is dissolved? (See Experiment 6.) Set the mixture aside for a few minutes, then note its appearance. Is starch soluble in cold water? What important difference between starch and sugar does this experiment show?
EXPERIMENT 16: THE EFFECT OF HEAT ON STARCH.—Hold to the light the starch and water mixture from Experiment 15. Is it opaque or transparent? Turn the mixture into a saucepan, heat, and stir it; return the mixture to the test tube or cup and again hold it to the light. What change was caused by heating it? Set the mixture aside for a few minutes. Have the starch and water separated as in the uncooked starch? Can you say it is insoluble, like uncooked starch? Can you say it is soluble, like sugar? What term indicating a half-dissolved condition can you apply to the cooked starch?