Approximate number of servings (b) Compare jellies, marmalades, pickles, and catsups as in (a). CARBOHYDRATES References: Sherman. Food Products. Hall, Mary Elizabeth. Candy Making Revolutionized. Farmers' Bulletin 93. Sugar as Food. Farmers' Bulletin 121. Beans, Peas, and Other Leg- umes as Food. Farmers' Bulletin 169. The Food Value of Beans. Farmers' Bulletin 244. The Cooking Quality of Pota- toes and Factors which Affect It. Farmers' Bulletin 295. Potatoes and Other Root Crops as Food. Laboratory Manual 63 Farmers' Bulletin 316. Cooking Cereal Foods. Farmers' Bulletin 342. Cooking of Beans and Other Vegetables. Farmers' Bulletin 517. Uses of the Sweet Potato. Farmers' Bulletin 535. Sugar and Its Value as Food. Farmers' Bulletin 565. Corn Meal as a Food and Ways of Using It. Langworthy. Green Vegetables and Their Uses in the Diet. Yearbook 191 7, pp. 439-452. General Classification of Carbohydrates Monosaccharids Disaccharids f Dextrose J Levulose I Sucrose Lactose Maltose Polysaccharids Starch Dextrin Glycogen .Cellulose Experiment 112. Properties of Carbohydrates. Examine the forms of carbohydrates given above, together with the commercial varieties of sugars, sirups, and starches at hand. Experiment 113. Chemical Reaction. (a) Test each one of the typical forms of carbohy- drate with Fehling's test, as follows : To J c water add J tsp of the material to be tested. Stir well with a glass rod. Heat. Add a few drops of 64 Preparation of Food the CuS04 solution, then add the KOH solution until the mixture takes on a bluish color. Boil. In which cases is there a precipitate formed (yellowish to red) ? What does this indicate ? (b) To a dilute solution of sucrose, made as above, add a few drops of lemon juice, vinegar, or other acid. Boil 5 minutes. Test as above. What change is brought about in sucrose by heating it with an acid ? To a mixture of starch and water add acid as above, but continue the boiling from 15 to 20 minutes, adding water to keep up to the original volume. Test. What is the effect of heating starch with an acid? What commer- cial use is made of this principle? (c) (Demonstration by instructor.) To a small quantity of cellulose (filter paper or fine cotton wool) add concentrated sulphuric acid slowly, with stirring, until the mass becomes homogeneous. Dilute with water. Boil 40 minutes to 1 hour. Test. What is the effect of strong acid upon cellulose? Experiment 114. Iodine Test. Test each carbohydrate as prepared in Experiment 113 by adding to a small portion, on a white plate, a drop or two of iodine. In which cases is there a blue coloration ? For what substance is this a test ? Laboratory Manual 65 SUCROSE Experiment 115. Solubility. (a) To i c of granulated sugar add sufficient cold water to dissolve. (b) To i c of granulated sugar add sufficient hot water to dissolve. Record amount of water necessary in each case. Experiment 116. Crystallisation. Mix solutions obtained above and add a little water. Divide into three portions, (a), (b), (c). Boil (a) 5 minutes, keeping original volume. Pour in bottle and let stand. To (b) add -J tsp of one of the acids suggested above. Boil 5 minutes, pour into bottle and let stand. To (c) add 25% glucose and boil as in (a) and (&). Let stand. Explain results. Experiment 117. Sweetening Power of Sugars.

AI-modernized reading of the original text

Approximate number of servings (b) Compare jellies, marmalades, pickles, and catsups as in (a). CARBOHYDRATES References: Sherman. Food Products. Hall, Mary Elizabeth. Candy Making Revolutionized. Farmers' Bulletin 93. Sugar as Food. Farmers' Bulletin 121. Beans, Peas, and Other Legumes as Food. Farmers' Bulletin 169. The Food Value of Beans. Farmers' Bulletin 244. The Cooking Quality of Potatoes and Factors which Affect It. Farmers' Bulletin 295. Potatoes and Other Root Crops as Food. Laboratory Manual Farmers' Bulletin 316. Cooking Cereal Foods. Farmers' Bulletin 342. Cooking of Beans and Other Vegetables. Farmers' Bulletin 517. Uses of the Sweet Potato. Farmers' Bulletin 535. Sugar and Its Value as Food. Farmers' Bulletin 565. Corn Meal as a Food and Ways of Using It. Langworthy. Green Vegetables and Their Uses in the Diet. Yearbook 191 7, pp. 439-452. General Classification of Carbohydrates Monosaccharids Disaccharids f Dextrose J Levulose I Sucrose Lactose Maltose Polysaccharids Starch Dextrin Glycogen .Cellulose Experiment 112. Properties of Carbohydrates. Examine the forms of carbohydrates given above, together with the commercial varieties of sugars, sirups, and starches at hand. Experiment 113. Chemical Reaction. (a) Test each one of the typical forms of carbohydrate with Fehling's test, as follows : To J c water add J tsp of the material to be tested. Stir well with a glass rod. Heat. Add a few drops of 64 Preparation of Food the CuS04 solution, then add the KOH solution until the mixture takes on a bluish color. Boil. In which cases is there a precipitate formed (yellowish to red) ? What does this indicate ? (b) To a dilute solution of sucrose, made as above, add a few drops of lemon juice, vinegar, or other acid. Boil 5 minutes. Test as above. What change is brought about in sucrose by heating it with an acid ? To a mixture of starch and water add acid as above, but continue the boiling from 15 to 20 minutes, adding water to keep up to the original volume. Test. What is the effect of heating starch with an acid? What commercial use is made of this principle? (c) (Demonstration by instructor.) To a small quantity of cellulose (filter paper or fine cotton wool) add concentrated sulphuric acid slowly, with stirring, until the mass becomes homogeneous. Dilute with water. Boil 40 minutes to 1 hour. Test. What is the effect of strong acid upon cellulose? Experiment 114. Iodine Test. Test each carbohydrate as prepared in Experiment 113 by adding to a small portion, on a white plate, a drop or two of iodine. In which cases is there a blue coloration ? For what substance is this a test ? Laboratory Manual 65 SUCROSE Experiment 115. Solubility. (a) To i c of granulated sugar add sufficient cold water to dissolve. (b) To i c of granulated sugar add sufficient hot water to dissolve. Record amount of water necessary in each case. Experiment 116. Crystallisation. Mix solutions obtained above and add a little water. Divide into three portions, (a), (b), (c). Boil (a) 5 minutes, keeping original volume. Pour in bottle and let stand. To (b) add -J tsp of one of the acids suggested above. Boil 5 minutes, pour into bottle and let stand. To (c) add 25% glucose and boil as in (a) and (&). Let stand. Explain results. Experiment 117. Sweetening Power of Sugars.

Selection and preparation of food