63 



T.\BLE 45. — Coinpodtion of dnj mailer offeceK from digestion experiments vrith macaroni. 



p;'m- 



§0 



503 

 504 

 505 

 513 

 514 

 515 

 597 

 598 

 599 

 588 

 589 

 590 



Whence obtained. 



E.xperiment No. 493 

 Experiment No. 494 

 E.xperiment No. 495 

 Experiment No. 49t) 

 Experiment No. 497 

 Experiment No. 498 

 Experiment No. .")92 

 Experiment No. 593 

 E.xperiment No. 594 

 Experiment No. 595 

 Experiment No. 59ti 

 Experiment No. 597 



Carbo- 

 hydrates. 



Per cent. 

 29. 92 

 37. 40 

 41.49 

 29. 69 

 39.07 

 29. 91 

 30.34 

 . 39.07 

 33.03 

 51.09 

 58. 90 

 51.14 



Ash. 



Per cent. 

 24.11 



23. 64 

 20. 87 

 30. 00 

 26. 93 



27. 43 



30. 44 

 28. .56 

 24.53 

 20. 75 

 15.66 

 15.89 



Heat of 



combvis- 



tion per 



gram. 



Calories. 

 4.879 

 5. 302 

 4.269 

 4. 197 

 5. 106 

 4. 240 

 4. 1.59 

 4. 776 

 4.993 

 4.774 

 4. 969 

 4. 920 



T.^BLE 46. — Amount, specific gravity, and nitrogen of urine from digestion experiments with 



macaroni. 



Whence obtained. 



Experiment No. 493 . 

 Experiment No. 494 . 

 Experiment No. 495 . 

 Experiment No. 496 . 

 E.xperiment No. 497 . 

 Experiment No. 498 . 

 Experiment No. .592 . 

 Experiment No. 593 . 

 Experiment No. .594 . 

 Experiment No. .595 . 

 Experiment No. 596 . 

 Experiment No. 597 . 



EXPERIMENTAL METHODS. 



The general plan of these digestion experiments was the same as 

 that for the comparison of the entire-wheat, graham, and straight- 

 grade breads, described on page 18. All of the food consumed for 

 a period of four days was weighed, .sampled, and analyzed, as well as 

 all the urine and feces pertaining to the experimental period. 



In the calculation of the digestibility of the macaroni and durum 

 wheat flour bread together, in the experiments made in 1904, and of the 

 macaroni in those made in 1905, the milk which formed part of the 

 ration was assumed to have the following digestibility: Protein, 97 per 

 cent; fat, 95 per cent; carbohydrates, 98 per cent; energy available to 

 the body, 95 per cent. These are the figures used in the digestion 

 experiments with bread and milk already described in this bulletin. 



The digestibility of the cereal alone in the experiments made with 

 the breakfast food prepared from durum wheat was computed on the 

 assumption that 97 per cent of the protein and 95 per cent of the fat 

 of the cream eaten with it were digested. 



