Human Foods and Their Nutritive Value Part 23

How does veal differ in composition from beef? 358. What general changes in composition occur as animals mature? 359. How do these compare with the changes that take place when plants ripen and seeds are produced?

360. How does mutton vary in composition from beef? 361. How does it compare in food value with beef? 362. How do lamb and mutton differ in composition? 363. To what extent do the various cuts differ in composition? 364. How do the more expensive cuts of lamb compare in nutritive value with the less expensive cuts? 365. How does pork differ in composition from other meats? 366. Give the general composition of ham. 367. Give the composition and nutritive value of bacon. 368. How does bacon compare in food value with other meats? 369. How does the character of the fat influence the composition and taste of the meat?

370. What influences the texture or toughness of meats? 371. How do cooked meats compare in composition with raw meats? 372. To what extent are nutrients lost in the boiling of meats? 373. What influence does the temperature of the water in which the meat is placed for cooking have upon the amount of nutrients extracted? 374. To what is the shrinking of meats in cooking due? 375. Of what does meat extract mainly consist?

376. To what do beef extracts owe their flavor? 377. What is their food value? 378. What is their dietetic value? 379. What is lard? 380. How does it differ in composition from other fats? 381. What is imparted to meats during the smoking process? 382. Why is saltpeter used in the preservation of meats? 383. Do vegetable foods contain nitrates and nitrites? 384. How does poultry resemble and how differ in composition from other meat? 385. Give the characteristics of sound poultry. 386.

Give the general composition of fish. 387. How does the flesh of different kinds of fish vary in composition? 388. What influence does salting and preservation have upon composition? 389. How do fish and meat compare in digestibility? 390. How does the mineral matter and phosphate content of fish compare with that of other foods? 391. What are the main nutrients in oysters? 392. Give the general food value of oysters. 393. What is meant by the fattening of oysters? 394. What effect does the character of the water used in fattening have upon the sanitary value? 395. Give the general composition of the egg. 396. How do different parts of the egg differ in composition? 397. How does the egg differ in composition from the potato? 398. Is color an index to the composition of the egg? 399. What effect does cooking have upon the composition of the egg? 400. What factors influence the flavor of eggs?

401. How do different ways of cooking affect the digestibility? 402.

Under what conditions can eggs be used economically in the dietary? 403.

Why should eggs be purchased and sold by weight? 404. How do canned meats differ in composition from fresh meats? 405. How do the nutrients of canned meats compare in cost with those of fresh meat? 406. What are the advantages of canned meats over fresh meats? 407. What are some of the materials used in the preservation of meats?

CHAPTER IX

CEREALS

408. How are the cereals milled? 409. What are the cereals most commonly used for food purposes? 410. Give the general composition of cereals as a cla.s.s. 411. What are the main nutrients in corn preparations? 412.

What influence does the more complete removal of the bran and germ of corn have upon its digestibility? 413. How does the cost of nutrients in corn compare with other foods? 414. Why is corn alone not suitable for bread-making purposes? 415. Why should corn be combined in a ration with foods mediumly rich in protein? 416. What change takes place in corn meal from long storage? 417. Give the characteristics and composition of oat preparations. 418. How does removal of the oat hull affect the composition of the product? 419. To what extent do the various oat preparations on the market differ in composition and food value? 420. Do oats contain any special alkaloidal or stimulating principle? 421. Why should oatmeal receive longer and more-thorough cooking than many other foods? 422. To what extent are the nutrients in oatmeal digested? 423.

How do wheat preparations differ in general composition from corn and oat preparations? 424. What influence upon the composition of the wheat breakfast foods has partial or complete removal of the bran? 425. What is the effect upon their digestibility and nutritive value? 426. What are the special diabetic flours, and how are they prepared? 427. What are the wheat middlings breakfast foods, and how do they compare in digestibility and food value with bread? 428. How do they differ mechanically? 429. How does barley differ from wheat in general composition? 430. What is barley water, and what nutritive material does it contain? 431. What cereal does rice resemble in composition? 432.

With what food materials should rice be combined to make a balanced ration? 433. What can you say as to comparative ease and completeness of digestibility of rice? 434. Why are cereals valuable in the ration?

435. In what way do they take a mechanical part in digestion? 436. What are predigested breakfast foods? 437. How would you determine the general nutritive value of a breakfast food, knowing the kind of cereal from which it was prepared? 438. To what extent are cereals modified or changed in composition by cooking? 439. To what extent are the nutrients of cereal foods digested and absorbed by the body? 440. To what extent do the cereals supply the body with mineral matter? 441. How does the phosphate content of cereals compare with that of meats and milk?

CHAPTER X

WHEAT FLOUR

442. Why is wheat flour especially adapted to bread-making purposes?

443. To what extent may wheat vary in protein content? 444. What are spring wheats? 445. What are winter wheats? 446. Give the general characteristics of each. 447. What are glutinous wheats? 448. What are starchy wheats? 449. Name the different proteids in wheat flour. 450.

About how much starch does wheat flour contain? 451. What other carbohydrates are also present? 452. What is the roller process of flour milling? 453. What is meant by the first break? 454. How are the different products of the wheat kernel separated? 455. What is meant by middlings flour? 456. What is break flour? 457. What is patent flour?

458. Name the high grade flours. 459. Name the low grade flours. 460.

How are the impurities removed from wheat flour? 461. What per cent of the wheat kernel is returned as flour? As offals? 462. What becomes of the wheat germ during milling? 463. What sized bolting cloths are used in milling? 464. What is graham flour? 465. How does it differ in mechanical and chemical composition from white flour? 466. What is entire wheat flour? 467. How does it differ in physical and chemical composition from white flour? 468. What effect has the refining of flour upon the ash content? 469. How do low and high grade flours differ in chemical composition? 470. How do the wheat offals differ in composition from the flour? 471. What are the factors which influence the composition of flours? 472. What effect does storage have upon the bread-making value of flour? 473. What change takes place when new wheat is stored in an elevator? 474. What is durum wheat flour, and how does it differ from other flour? 475. What gives flour its color? 476. Why is color an index of grade? 477. How is the color of a flour determined?

478. How do flours differ in granulation? 479. How does the granulation affect the physical properties of flour? 480. How is the granulation of flour approximately determined? 481. How is the absorptive capacity of a flour determined? 482. What factors cause a variation in the capacity of flours to absorb water? 483. Give the characteristics of a good gluten.

484. What causes unsound flours? 485. How is the bread-making value of a flour determined? 486. How are flours bleached? 487. How does bleaching affect the chemical composition of flour? 488. What influence does bleaching have upon bread-making value? 489. Traces of what compounds are formed during bleaching? 490. Are these compounds injurious to health? 491. What effect does bleaching have upon the color of fiber and debris particles in flour? 492. Is it possible to bleach low grade flours and cause them to resemble high grade flours? 493. Are flours usually adulterated? 494. Why? 495. How would mineral adulterants be detected? 496. How would the presence of other cereals be detected? 497.

How does flour compare in nutritive value with other foods? 498. How does the cost of flour compare with that of other foods? 499. What causes flours to vary so in bread-making value? 500. Why may flours produced from the same type of wheat vary slightly in character from year to year? 501. What relations.h.i.+p exists between the nutritive and bread-making value of a flour?

CHAPTER XI

BREAD AND BREAD MAKING

502. Define leavened and unleavened bread. 503. Why is yeast used in bread making? 504. Give the characteristics of a good loaf of bread.

505. Why is flour used for bread making purposes? 506. Name the eight chemical changes that take place during bread making. 507. To what extent do losses in dry matter occur during bread making? 508. What compounds suffer losses during bread making? 509. What is yeast? 510.

What chemical changes does it produce? 511. What becomes of these products during bread making? 512. How is compressed yeast made? 513.

What part does the alcohol take in bread making? 514. What temperature is reached in the interior of the loaf during bread making? 515. Through what chemical changes does starch pa.s.s during bread making? 516. To what extent are soluble carbohydrates formed? 517. In what way is starch acted upon mechanically? 518. Explain the structure of the starch grains in flour and in dough after they have been acted upon by the yeast ferments. 519. To what extent are acids produced in bread making? 520.

What becomes of the acids formed? 521. How may the acids thus developed affect the properties of other chemical compounds? 522. To what extent are volatile carbon compounds, other than carbon dioxid and alcohol, liberated during bread making? 523. What changes occur to the various proteids during the process of bread making? 524. Why do flours vary in quality of gluten? 525. To what extent do losses of nitrogen occur during bread making? 526. How much of the total nitrogen of flour is present as proteids? 527. How is the fat of flour affected during the process of bread making? 528. What effect does the addition of 10 per cent of wheat starch to flour have upon the size of the loaf? 529. What effect does the addition of 10 per cent of wheat gluten to flour have upon the size of the loaf? 530. What relations.h.i.+p exists between gluten content and capacity of a flour to absorb water? 531. Give the general composition of bread. 532. What factors influence its composition? 533.

What effect does the use of skim milk and lard in bread making have upon composition? 534. How does the temperature of the flour influence the bread-making process? 535. Why is it necessary to vary the process of bread making in order to get the best results with different kinds of flour? 536. To what extent are the nutrients of bread digested? 537. How does graham bread compare in digestibility with white bread? 538. How do graham and entire wheat breads compare in nutritive value with white bread? 539. What value do graham and entire wheat breads have in the dietary? 540. Why is white bread generally preferable in the dietary of the laboring man? 541. How do graham and entire wheat flours compare in chemical composition with white flour? 542. How do they compare in mechanical composition? 543. To what is the difference in digestibility supposed to be due? 544. Are graham and entire wheat breads necessary in a ration as a source of mineral elements? 545. What is the main difference in composition between old and new bread? 546. How do different kinds of bread made from the same flour compare in composition and nutritive value? 447. How does toast differ in composition from bread? 548. What influence does toasting have upon digestibility? 549.

What is gained by toasting bread? 550. How does bread compare in nutritive value with other cereal foods? 551. How does bread compare in nutritive value with animal foods?

CHAPTER XII

BAKING POWDERS

552. What is a baking powder? 553. What are the two kinds of materials which baking powders contain? 554. Name the different types of baking powders. 555. How does baking powder differ in its action from yeast?

556. What are the cream of tartar baking powders? 557. What is the nature of the residue which they leave? 558. What are the phosphate baking powders? 559. What is the nature of the residue which they leave? 560. Why is the mineral phosphate not considered equally valuable with that naturally present in foods? 561. What are the alum baking powders? 562. What residue is left from the alum powders? 563. Which of the three cla.s.ses of baking powders is considered the least objectionable? 564. Why is a new baking powder preferable to one that has been kept a long time? 565. Why should baking powders be kept in tin cans, and not in paper? 566. Why are fillers used in the manufacture of baking powders? 567. How may a baking powder be prepared at home? 568.

How does such a baking powder compare in cost and efficiency with those purchased in the market?

CHAPTER XIII

VINEGARS, SPICES, AND CONDIMENTS

569. What is vinegar? 570. How is it made? 571. Give the three chemical changes that take place in its preparation. 572. Why is air necessary in the last stage of the process? 573. What ferments take part in the production of vinegar? 574. What is malt vinegar? 575. What materials other than apples can be used in the preparation of vinegar? 576. Give the characteristics of a good vinegar. 577. In what ways are vinegars adulterated? 578. What food value has vinegar? 579. Why should vinegars not be stored in metalware? 580. What dietetic value has vinegar? 581.

To what materials do the spices owe their value? 582. What is pepper?

583. What is the difference between white and black pepper? 584. What compounds give pepper its characteristics? 585. How are peppers adulterated? 586. What is mustard? 587. Give its general composition.

588. How is it adulterated? 589. What is ginger? 590. How is it prepared for the market? 591. Give its general composition. 592. What is cinnamon? 593. What is ca.s.sia? 594. What gives these their taste and flavor? 595. What are cloves? 596. How are they prepared? 597. What is mace? 598. What is nutmeg? 599. Do the spices have any food value? 600.

What is their dietetic value? 601. Why is excessive use of some of the spices objectionable?

CHAPTER XIV

TEA, COFFEE, CHOCOLATE, AND COCOA

602. What is tea? Name the two plants from which it is obtained, the countries where each grows best, and the number of flushes each yields.

603. Upon what does the quality and grade of tea depend? 604. Give differences in the preparation and composition of green and black teas.

605. The characteristic flavor of tea is imparted by what compound? 606.

To what compound are its peculiar physiological properties due? 607.

What can you say of the protein in tea as to amount and food value? 608.

Why should tea--especially green tea--be infused for a very short time, never boiled? 609. What effect has tannin upon the digestion of proteids? 610. What three points are considered in judging a tea? 611.

What is the most common form of tea adulteration? 612. Describe the coffee plant and fruit, and its method of preparation for market. 613.

What is the difference in the chemical composition of tea and coffee?

614. Name the characteristic alkaloid of coffee. How does it compare with theme? 615. Why may coffee not be considered a food? 616. Tell different ways in which coffee may be adulterated. 617. Which is more commonly practiced, tea or coffee adulteration? Why? 618. How may real coffee be distinguished from chicory? Why? 619. Name the three kinds of coffee in general use. Give distinguis.h.i.+ng features of each. Which is usually considered best? 620. From what are cocoa and chocolate obtained? 621. Give the two methods of preparing cocoa. 622. What alkaloid similar to the theme and caffeine of tea and coffee is present in cocoa and chocolate? 623. What is the difference in preparation of cocoa and chocolate? 624. What are cereal coffee-subst.i.tutes? 625. What nutritive value have they? 626. How do they differ in composition from coffee? 627. To what extent does cocoa add to the nutritive value of a ration? 628. What is plain chocolate? 629. Why do chocolate preparations vary so widely in composition? 630. What treatment is given to the cocoa bean in its preparation for commerce? 631. What treatment is sometimes given to prevent separation of the cocoa fat? 632. In what ways may cocoa and chocolate preparations be adulterated?

CHAPTER XV

DIGESTIBILITY OF FOODS

633. Define the term nutrient. 634. Do all the nutrients of food have the same degree of digestibility? 635. What is a digestion coefficient?

636. How is the digestibility of a food determined? 637. What volatile products are formed during the digestion of food? 638. Define digestible protein; digestible carbohydrates, digestible fat. 639. What is the available energy of a ration? 640. How is it determined? 641. How do the nutrients, protein, fat, and carbohydrates, compare as to available energy? 642. Why is it necessary to consider the caloric value of a ration? 643. Is the protein molecule as completely oxidized in the body as starch or fat? 644. What residue is left from the digestion of protein? 645. What part do the soluble ferments take in digestion? 646.

To what extent are the nutrients of animal foods digested? 647. Which nutrient, protein or fat, is the most completely digested? 648. How do vegetable foods compare in digestibility with animal foods? 649. What effect does cellulose have upon digestibility? 650. Which of the nutrients of vegetables, protein or carbohydrates, is more completely digested? 651. What mechanical value may cellulose have in a ration?

652. Why must bulk be considered in a ration, as well as nutrient content? 653. Name the eight most important factors influencing the digestibility of foods. 654. To what extent does the combination of foods affect the digestibility of the nutrients? 655. Why does a mixed ration give better results than when only a single food is used? 656.

How does the amount consumed affect the completeness of the digestive process? 657. To what extent does the method of preparing food affect digestibility? 658. What is gained, so far as digestibility is concerned, by the cooking of foods? 659. To what extent does the mechanical condition of food affect its digestibility? 660. Why is it desirable to have some coa.r.s.ely granulated foods in a ration? 661. Why should the ration not be composed exclusively of finely granulated foods? 662. Why is some coa.r.s.ely granulated food more essential in the dietary of the sedentary than in the dietary of the laborer? 663. How does palatability affect the digestive process? 664. Do psychological processes in any way affect digestion? 665. What physiological properties do some foods possess? 666. To what are these physiological properties due? 667. To what extent is individuality a factor in digestion? 668. To what extent does digestibility differ with individuals? 669. Why do some foods affect individuals in different ways? 670. Why is it necessary that the quant.i.ty, quality, and character of the food should vary with different individuals? 671. In what different ways is the expression "digestibility of a food" used? 672.

Why is it necessary to consider the digestibility of food, as well as its composition? 673. Does the digestibility of a food necessarily indicate the economic uses that will be made of it by the body? 674. How is it possible for one food containing 10 per cent of digestible protein, and other nutrients in like amounts, to be more valuable than another food with the same per cent of digestible protein and other nutrients? 675. How is it possible for one food to contain less total protein than another food and yet be more valuable from a nutritive point of view? 676. Why is it necessary to consider the mechanical condition of a food and its combination with other foods, as well as its chemical composition? 677. What effect does lack of a good supply of air have upon the completeness of the digestion process? 678. In what ways does the digestion of food resemble the combustion of fuel? 679. What is gained by a study of the digestibility of foods? 680. Why may two foods of the same general character give different results when used for nutritive purposes?

CHAPTER XVI

COMPARATIVE COST AND VALUE OF FOODS

681. To what extent do the nutritive value and the market price of foods vary? 682. How is the value of one food expressed in terms of another food? 683. How determine the amount of nutrients that can be procured in a food for a given sum of money? 684. How compare the amounts of nutrients that can be procured in two foods for a given sum of money?