1921.] Wright.—Chemical Technology of Meat Industry. 
81 
nitrogenous constituents while the prolonged heating of the material is 
taking place. It is only when the peptone-like bodies are produced in 
relatively large amounts that the bitter flavour can be noted. 
The valuable constituents of a meat-extract are the so-called “ meat 
bases,” which are the products of the breaking-down of proteins in the 
vital processes of the body. They are excreted for the most part unchanged, 
and have little value as builders of tissue. They cannot be strictly regarded 
as foods, but possess certain stimulating properties, and apparently furnish 
relief to fatigued muscle and are powerful excitants of gastric secretion. 
It is of the utmost importance to proceed with the concentration of the 
extract liquor with all possible despatch, for the dilute solutions afford 
suitable media for bacterial growth. However, if the liquor is not allowed 
to cool down or to remain at a temperature which allows bacterial develop¬ 
ment to take place no decomposition can occur. Once, however, the con¬ 
centration is secured, extract of meat is, in its nearly solid state, no longer 
a medium suitable for bacterial growth. Commercially it is known that 
even after a period of several years solid meat-extract has been found 
to be undeteriorated. The results of bacteriological and chemical experi¬ 
ments clearly show that solid meat-extract is a non-putrescible substance, 
and confirm the evidence of commercial observation upon this point. 
The following results show the typical composition of a well-prepared 
meat-extract . Meat-extract. 
Table III . Per Cent. 
Moisture . . . . .. .. 21*79 
Organic matter . . .. .. .. 59*95 
Salt .. .. .. .. .. 3*36 
Other mineral salts .. .. .. .. 14*90 
Total nitrogen .. .. .. .. 8*72 
Fat .. .. -.. . . .. 0*33 
Acidity as lactic acid .. .. .. 10*50 
Soluble in 80 per cent, alcohol .. .. 57*42 
Insoluble in 80 per cent, alcohol . . .. 30*79 
Meat bases .. .. .. .. .. 14*00 
Edible Fats. (3, 4, 5, 6, 8, 17, 21.) 
The edible fats are manufactured from the fats removed from the 
visceral cavity of sheep, lambs, and cattle. These fats are principally the 
“ caul ” and kidney. 
The fats after removal from the carcase are thoroughly washed in water 
which is tepid, in order to remove any adherent blood and other impurities. 
The fats are then immersed in ice-cold water, so that they may be hardened. 
The hardened fats are then cut up into fine mass, and the material so 
disintegrated is transferred to a jacketed melting-pan provided with slowly 
moving mechanical agitators. 
In melting a fat for edible purposes the most satisfactory temperature 
for rendering is that which is as little above the melting-point of the fat 
as possible. In practice, however, this course cannot usually be followed, 
on account of the length of time which is required to adequately render 
the fats. It is the custom, therefore, to carry out the rendering at tem¬ 
peratures of from 130° to 165° F. The higher temperature is, however, 
prone to produce unsatisfactory results in regard to quality, but a greater 
yield may sometimes be obtained. 
When the fats are thoroughly melted the mass is allowed to settle, 
and salt is sprinkled over the surface of the liquid to assist the 
6—Science, 
