87 



meat juice and meat fiber cooked in different ways. 

 Series XIV.^Expeuimexts Nos. 148, 149. 



The object of this series was (1) to dotennine, if possil)!*', whether it 

 is the soluble or the insoluble constituents of meats which upon cook- 

 ini,^ are so chanjjfed as to produce the characteristic flavor of cooked 

 meats, and (2) to learn whether or not the insoluble constituents of 

 meat are made solul)le by the process of cooking. No experiments 

 of this nature liave been tluis far reported in connection with the 

 nutrition investigations made in this laboratory. Fresh U'an ))eef 

 round, from which all bone, gristle, and visible fat were removed, was 

 selected. The entire cut, weighing about ."> poutids, was divided into 

 strips and then passed through a sausage mill four times, lu'lng mixed 

 well after each grinding. A sample (No. 1677) of the thoroughly mixed 

 meat was reserved for analysis, the results of whicli are given in the 

 tables in connection with cooking experiment No. I-IH (pp. IHMM). 



The remainder of the finely divided meat was used for the prepara- 

 tion of meat juice and meat Kl)er, as follows: The entir(> (juantity, 

 about 4.5 pounds, was placed in a compound screw press, in portions 

 weighing about 1.75 pounds each, and subjected to as nuich i)ressure 

 as possible. Al)out 700 cubic centimeters of meat juice were obtained. 

 The meat liber was now thoroughly moistened with cold distilled 

 water (700 cubic centimeters), intimately mixed ])y kneading with 

 the hands for thirty minutes, and again pressed, yielding about 800 

 cubic centimeters of liquid. The material remaining in the press 

 w^as again moistened with water (700 cubic centimeters) and pressed, 

 wdien about 900 cubic centimeters of li<iuid were recovered. The three 

 quantities of liquid thus removed were combined, making 2,300 cubic 

 centimeters in all, diluted with water to 2,500 cubic centimeters, 

 thoroughly mixed, set aside, and designated sample No. 1678. The 

 meat liber left after pressing out the juice (sample No. 1679) was used 

 for cooking experiment No. 149. 



Cooking Experimext No. 148. 



The meat juice (sample No. 1678) w^as divided into six portions of 

 400 cubic centimeters each. One portion of the fresh juice was sub- 

 jected to complete analysis in triplicate, the results ol)tained being- 

 given in Tables Nos. 90 and 91. The results have been calculated to 

 show the amount of the difl;erent kinds of nitrogenous constituents 

 and the total quantity of proximate constituents in 2,500 cubic centi- 

 meters of the meat juice. 



