CHANGES IN FRESH BEEF DURING COLD STORAGE. 13 
the nature and quantity of the soluble constituents of the muscles, either in 
fresh condition or after autolysis or cold storage. 
The solvent used was 0.9 per cent aqueous solution of sodium chlorid that 
had been saturated with thymol by shaking with a concentrated chloroform 
solution of that substance. The preparation of the extract in these experiments 
was always begun as soon as possible after the grinding of the samples. The 
entire process was carried on in refrigerated rooms, the preparation of the 
extract at a temperature between 34° and 45° F., and subsequent extraction 
at a temperature between 34° and 36° F. The solvent was cooled to about 
34° F. before use. 
One hundred grams of the finely ground meat were weighed into a beaker 
and transferred quantitatively, with the aid of some of the solvent, to a 7-inch 
porcelain mortar. The meat was mascerated with the solvent to a smooth 
pulp, and quantitatively transferred to a 2,000 c. c. volumetric flask with the 
aid of a stream of the solvent from a wash bottle. The contents of the flask 
were then diluted to the mark with the isotonic solution, and the flask was 
placed in a cold-storage room at a temperature between 34° and 36° F. The 
suspension thus prepared was shaken at intervals of not less than an hour 
during the remainder of the day, and at like intervals during the morning of 
the following day, until at the expiration of the twenty-third hour it had been 
shaken on eight different occasions. After settling for another hour, it was 
filtered, the clear filtrate being used for the determination of the soluble con- 
stituents of the meat. 
A determination of the volume displaced by the insoluble material has con- 
vinced us that the error caused by its presence is negligible. 
Total solids were determined by evaporating 50 c. c. of the extract to dryness 
in a platinum dish on a steam bath, and by subsequently drying to constant 
weight at 100° C. Correction was made later for the sodium chlorid contained 
in the extract. 
Ash. — The residue from the determination of total solids was carefully 
charred in an electric furnace, the temperature being kept below 600° C. in 
order to guard against volatilization of sodium chlorid. The charred mass was 
extracted with hot distilled water, filtered, washed, and the residue then 
ignited in the original dish. The filtrate was then transferred to the dish, 
evaporated to dryness, dried at 150° C. for several hours, and finally ignited 
for a short time at a temperature under 600° C. The dish was covered during 
ignition to avoid loss by decrepitation. Correction was made for the sodium 
chlorid content of the ash. 
Sodium chlorid. — The ash was extracted with hot water, the filtrate made 
to volume, and sodium chlorid was determined in an aliquot portion by means 
of a standard solution of silver nitrate, with potassium chromate as an 
indicator. 
Organic extract was obtained by substracting the percentage of ash from 
that of total solids. 
Total soluble nitrogen was determined in 100 c. c. of the extract by the 
Kjeldahl-Gunning method. 
CoagulaUe nitrogen. — One hundred cubic centimeters of extract was trans- 
ferred to a 150 c. c. beaker, heated on a steam bath until the protein had 
coagulated, and then neutralized to litmus paper by the addition of a standard 
solution of sodium hydroxid. The solution was then heated on the steam bath 
until the original volume had been reduced by about one-third, after which it 
was filtered and the precipitate washed with hot water until free from sodium 
chlorid. Nitrogen was then determined in the precipitate. 
