BEEF EXTRACT. 



1389 



It thus appears that less proteid matter is extracted when meat is 

 plunged into boiling water or water that is quickly heated to the boil- 

 ing point than when it is packed into a can and the can exposed to a 

 temperature but little above the boiling point of water. In the for- 

 mer case the soluble proteids near the surface of the meat are coagu- 

 lated before they can diffuse into the surrounding water, while in the 

 latter case, owing to the low conductivity of meat, the temperature at 

 the surface of the can rises slowly, and the juice which is driven from 

 the meat carries with it much proteid matter in solution, to be precipi- 

 tated by coagulation from the liquor surrounding the meat when a 

 sufficiently high temperature is reached. 



Parboiling, therefore, or "shrinking," as it is technically called, is 

 practiced, because to produce a marketable article it is necessary that 

 beef be cooked before it is canned. As has been previously shown, it 

 detracts little from the muscle-forming element of the meat. The 

 only substances removed are water, fat, soluble ash, and meat bases. 

 Of these, fat is useful in supplying fuel for body heat, and the meat 

 bases, and perhaps the soluble ash, may have some value as stimulants. 

 (See beef extract, below.) 



Parboiling also serves another purpose. By removing a large quan- 

 tity of water it increases the relative percentage of nutritious com- 

 pounds and thus forms a somewhat concentrated food. This is best 

 illustrated in Table 8, which gives the number of ounces of beef 

 found in each can and the number of ounces of fresh beef used in its 

 preparation. 



TABLE 8. Equivalents of fresh and canned beef. 



Thus a can of 30 ounces of roast beef contains the equivalent of 48.9 

 ounces of fresh beef (average), and would contain practically every- 

 thing of value in the fresh beef with the exception of a portion of 

 the fat. 



BEEF EXTRACT. 



The "soup liquor" (the water in which the meat has been parboiled 

 previous to canning) was formerly discarded and allowed to run into 

 the sewer. During the last few years, however, its value was greater 

 than that of the fuel necessary to its evaporation, and it has been used 



