MUSCLE, AND EXTRACTIVES. 345 



were generally reported as showing more or less " peptone " 

 when, according to the present views, " albumose " is meant. 

 The following figures may be taken as representing approxi- 

 mately the average composition of typical samples of Ameri- 

 can meat extract : 



Water 20.0 



Inorganic salts (ash) 22.5 



Albumose (and gelatin) 16.5 



Flesh bases, etc 26.4 



N-free extractives 14.6 



According to these results the food value of the extract 

 would be measured by the nitrogen-free extractives and the 

 albumose and gelatin fractions. In some kinds of extract the 

 flesh bases and related bodies are much higher than here given, 

 with corresponding diminution in the other organic constitu- 

 ents. The real value of these extracts lies mainly in other 

 directions, however. They contain the flavoring and stimu- 

 lating portions of the meat, and should not be considered so 

 much as foods as additions to foods. Added to vegetables 

 they impart an agreeable taste and doubtless serve a very 

 useful purpose in stimulating appetite for substances not in 

 themselves possessing much flavor. In their action the basic 

 and similar substances in the meat extracts may be perhaps 

 fairly compared with the alkaloids in tea and coffee, which, 

 experience shows, have a real value. Large amounts of the 

 extracts cannot be used, however, as foods, because of the 

 presence of the large percentages of alkali phosphates and 

 other salts. A few simple experiments may be made to show 

 some of the properties of the common commercial extracts. 



Ex. Heat a little of the solid extract on a piece of porcelain until it 

 is reduced to a char. Extract this with dilute nitric acid, filter and divide 

 the filtrate into two portions. In one test for phosphates by the addition 

 of ammonium molybdate and in the other for potassium salts by the 

 flame test. Both reactions should be very distinct. 



Ex. Dissolve 20 grams of extract in water to make about 200 cubic 

 centimeters. A nearly clear solution should be obtained, showing absence 

 of fat or coagulated protein. To a few cubic centimeters add enough 



