=4. Cheese crackers.=——Select crackers of a firm quality that will not crumble or flake easily, and of a small size. Spread very thinly with soft butter, put the crackers in a pan, and sprinkle grated cheese upon each one. Set the pan in a moderate oven until the cheese is melted. A sprinkling of paprika may be used. Serve with lettuce, celery, or other green salad. EXERCISES 1. Compare the composition of eggs, milk, and cheese. 2. How may an egg which has been kept too long in cold storage be detected? 3. What is the effect of the boiling temperature of water upon an egg? 4. Compare a hard- and a soft-cooked egg for digestibility. 5. What are the dangers from unclean milk? 6. How may the milk supply be safeguarded? 7. Why is cheese a meat substitute? 8. What caution should we exercise in using it? 9. What precaution must we take in cooking cheese? CHAPTER X THE FATS AND THE SUGARS Fats are composed of carbon, hydrogen, and oxygen, but have much more carbon than the other kinds of foodstuffs. Notice in Fig. 46 that olive oil and lard are pure fats; the other fat foods containing water, protein, and ash. Fat is available in various forms, with differing flavors and a wide range of prices. To many people it is unpalatable in some of its cheapest forms; yet its use is important, and some kind should be included in the diet. Fluid and emulsified fats are the most easily digested, hence olive oil, cream, and egg yolk are highly desirable. Bacon and butter belong nearly in the same class. A vigorous man at hard labor can digest fat of any kind without difficulty, and needs it because it gives so much fuel in proportion to its bulk. Fat tends to retard gastric digestion, and delicate persons must be careful about taking with it other foods which are hard to digest, or taking it in the form of fried foods, pastries, rich cakes, and sauces. Persons with delicate appetite, who lose weight because they do not get enough fuel, may be benefited by taking a little more fat in the diet, especially if they do not digest starch and sugar readily, but a very large amount (over 6 or 7 ounces a day) will not be perfectly digested. =Fat as a food.=——_Beef fat_, as it occurs with lean, is a digestible fat. If thoroughly browned in the cooking process, it is most palatable, and the taste for it should be cultivated. In gravy, it may be used with potato, instead of butter. Fat tried out from suet, may be used in place of butter as an ingredient in some puddings, and even in batter mixtures. It may also be used with vegetables when the price of butter is prohibitive. See Fig. 47. [Illustration: FIG. 46.——Composition of fat foods.] [Illustration: FIG. 47.——100-Calorie portions of fat foods. WEIGHT OF PORTION No. KIND OUNCES