43 



and skin and thoroughly ground ami mixed by passing six times through a meat 

 chopper. It was i hen divided into two equal portions, one marked "fresh" and the 

 other, after the addition of 0.1 per cent of boric acid, was marked ''preserved." 



Tin- third .-ample represents the meat from three cold-storage drawn chickens, in 

 :e twenty-.-ix immihs, treaied in the same manner as above, but without the ad- 

 dition of boric acid, and marked "stored." Each sample was placed in a screw-cap 

 i jar and allowed to stand for one week, at laboratory temperature during the day, 

 and in an ice box at nielli. During this time samples were taken for analysis on the 

 tirsi, .-econd, third, sixth, and seventh days of standing. Every precaution was ob- 

 1 toward against loss of moisture during the removal of the sample, as a result 

 of whieh the moisture content remained very constant. 



M KTHODS. 



The following deierminat ions were made at each of the periods cited: Moisture, 

 loud niiro-en, ammonia nitrogen, ami. in the aqueous extract afroorn temperature 

 and with i-- water, nitn : termined as total, coagulable, amido, and ammo- 



nia. The difference between the <nm of the coagulable and amido nitrogen and the 

 toi.il soluble niiro-rn i- . -..n id- n d as proteoeesand peptones. The fat was determined 

 : of the experiment. 



.I/.I/A/// /- w.i- determined on a 2-gram sample, dried in a water oven for ten hours. 

 Tin- ! \e < alculated as moisture. 



The dried <amulr from the moisture determination was ground with dry sand 

 and xtr.ici.-d wiih anhydrous ether in a Knorr extractor for twenty-four hours for 

 'ermination oJ 



'ininaiion- w. re made in the Nitrogen Section of the Bureau of Chem- 

 by Mr. 11 \\ . llon-hton, u<iii'4 the (InnniiiL,' modification of the Kjeldahl method. 

 The nim >gcn was determined on from 5 to 10 grams of sample distilled 



from i he addition of iT><)-300 cc water and 10 grams magnesium 



dlate was colic, ted in standard acid and the ammonia nitrogen de- 

 termined afi.-r .1 on, --half hour distilling. r><> cr being distilled off. The distillation 

 "titinned for thn-,- half-hour period-, i">0 cc of water being returned to the flesh 

 M h distillation. The results reported represent the sum of the three half- 

 hour pen 



l ti-mfHriitur? (^>-^5 C.) and with ice water (8 C.)]: 



imple of meat were weighed into a 450 cc Erlen- 



ided, and shaken for three hours in a shaking machine. 



Iniheca-. chopped ice was added from time to time, the volume 



in the ila-k l>eni'_ r k. , nf by decanting the excess of water into a second flask. 



ken ihe n-quired length of time, the Ilasks were placed in the refrigera- 

 toi -over niu'lu. a -mall ijuaniiiy of thymol and phenol having been added as a preserva- 

 tive. The IM-\I day they were poured through linen bags and extracted with room 

 temperan; ; ively, by vigorous manipulation with the hands 



and BUCCenive porti ter, till th final extract gave a negative biuret reaction. 



The extraction u-dioiis and re(jiiired, at first, an entire day for completion, 



usiiiu'iron. -of rM)m-temj)eratnro water, and from 1,800 to 2, 000 cc of ice 



m-temperatnre exuact was made up to avolumeof 2,500 cc, while the 

 Ice- water < made upt)L'.o<H)cc throughout theexperiment, though the latter 



iticularly on the last two dayn, were completed with from 1,400 to 1,800 

 After making to volume and thoroughly mixing, the solutions were filtered 

 through Ji-im-h funnels containing a 38.5 cm S. & S. 588 folded filter paper. The first 

 which ran through was discarded (in the case of the room-temperature extract 

 this was used fnr the ammonia determination); the second quantity, 600 cc to 800 cc, 



d for the water-soluble nitrogen determinations. 



The nitration of the .-..Intions of the first three extractions was very simple, the 

 solutions running through the paper readily, though the second portion was still 

 somewhat cloudy. As the samples spoiled, the extraction became more easy and 

 the nitration more difficult, until on the last two days it was quite difficult to 

 obtain sntiicient s .lution to make the determinations. This filtered extract was 

 entirely clear. The total nitrogen in the aqueous extract was made on 100 cc of 

 -"lution 



nonia nltrn,,,,, was determined on 500 cc of the room temperature extract, by 

 distillation with magnesium oxid. 



