5. How may we best retain the mineral matter of vegetables in cooking? 6. Is it allowable to cook a vegetable in boiling water and throw away the water? 7. Why must more time be allowed for baking a potato than for boiling? 8. Why more time for an old beet than for a young? 9. Find the cost of potatoes in your locality. Estimate the cost of a dish of mashed potato for five people. 10. Estimate the cost of 100-Calorie portions of several vegetables. See Fig. 36. CHAPTER VIII CEREAL PRODUCTS The common grains, sometimes called cereals,[11] yield some of the most important of all the food materials. Those most widely used are wheat, maize, or Indian corn, oats, rice, barley, rye, and millet. In this country wheat and corn are the two great crops upon which our prosperity largely depends, and a shortage in one of these crops is felt in the business world, not only in this country, but abroad. Rice is the important cereal in China, Japan, and India, and a failure of the rice crop may mean famine to millions of people, especially in India. These facts are mentioned to show that the race has learned to depend upon the grains as a staple food, and a study of their composition proves that this common habit is founded in reason. The grains are all members of the grass family, and the edible portion is the seed. From these seeds are manufactured pure starch, breakfast cereals, meal, and flour. Like beans and peas, these seeds are the storehouses of food for the young plants, and we therefore find the high nutritive value depicted in Fig. 37. Notice that the carbohydrate (starch) content is high in all; that all contain protein, oats, wheat, and rye being about equal in this and higher than the others; oats are highest in fat, corn ranking next. The ash contains the same important mineral substances that we found in the fruits, the percentages of each differing somewhat with the different grains and being quite different for the cereals as a class than for the fruits and vegetables as a class. It must be remembered that these percentages are given for the whole grain, and that the amounts of the nutrients in the manufactured product depend upon the process employed. =Manufacture of cereal food materials.=[12]——The primitive method of making the material in the grain available for use was by grinding the grain between two stones, or by pounding one stone upon another, and this method is used by the Mexicans and certain of the American Indians to this day, human muscle being the power employed. Wind and water were harnessed for grinding grain, and were the only motive powers available until the invention of steam, the grinding being done by stones. In a Connecticut town there still exists a mill stone, one of a pair so small that they were carried into the settlement on horseback, and when placed in a small mill by a brook, they ground a bushel of corn in a day.