2 Journal of Agricultural Research voi.xvii. No. r 



to all intents and purposes was practically the same in its essential 

 features as that in use in the general commercial preparation of these 

 articles. For the purpose of clarification "roast-beef soak water," 

 " defibrinated blood," and "blood water," were added during the process 

 of manufacture in all cases with the exception of the extracts prepared 

 from cured meat. The comparatively large quantities employed of 

 these agents necessarily influenced the composition of certain of the 

 extracts, particularly those prepared from livers and spleens, and extracts 

 of the various organs and tissues, therefore, were prepared in the labo- 

 ratory, the method followed being nearly identical with the commercial 

 process. Practically the only exception was the replacement of the 

 materials commercially used in clarifying the extracts with those of a like 

 composition, equally efficient, but derived from the specific tissue or 

 organ under investigation. A detailed description of the laboratory 

 process follows. 



LABORATORY METHOD 



The finely minced material from which the extract was prepared was 

 placed in a large tin-lined box and iced water added until the minced 

 meat was well covered. The box with its contents was then placed in 

 the refrigerator where it was allowed to remain overnight, when the 

 resulting "soak water" was drawn off and reserved for clarifying pur- 

 poses. The partially extracted minced meat was then transferred to a 

 large open kettle provided with a perforated steam coil, an equal weight 

 of water added, and steam slowly applied, the temperature being grad- 

 ually raised to 95° to 97° C, and the liquid kept in constant agitation 

 by the entrance of the steam from the perforated pipe. 



This extraction was continued for 45 minutes, after which the liquid 

 was drawn off, cooled, and transferred to an evaporating kettle provided 

 with a closed-coil steam pipe. The "soak water" obtained as above 

 was then added, the whole brought to a boil, and the evaporation con- 

 tinued until the liquid was reduced to two-thirds of its original volume, 

 the coagulable proteids which form a scum upon the surface of the liquid 

 being removed from time to time. After this concentration the liquid 

 was filtered and transferred to a vacuum kettle where it was evaporated 

 under reduced pressure until the extract was of the desired consistence. 

 This method yielded extracts identical in physical appearance and organo- 

 leptic properties with those obtained by the commercial process. 



As it was also considered desirable to obtain data regarding possible 

 differences in extracts prepared from cold and hot water extractions, 

 the process described above was modified in the case of chuck and plate 

 extracts prepared in the laboratory. Chuck and plate extract 29 was 

 prepared by repeatedly exhausting the minced meat with large quan- 

 tities of cold water and then concentrating the extract. Chuck and 

 plate extract 30 was prepared by placing the minced meat in an equal 



