Wright. — Chemical ConipoRifinn of Meat-extract. 



The following tahle shows the composition of the mineral salts of the 

 extract examined : — 



The moisture-content as laid down by Liebig should not exceed 21 per 

 cent. The total mineral salts, according to the same authority, should vary 

 from 15 to 25 per cent. The mineral salts found in true meat-extracts are 

 potassium-dihydrogen-phosphate, potassium-monohydrogen-phosphate, and 

 the sulphates of calcium, potassium, and sodium, and the chlorides of sodium 

 and potassiu.m. Chloride of sodium is a minor constituent of meat-extract, 

 the chlorine being present almost entirely as the potassium-salt. Salt is 

 sometimes added to extract of meat in order, it is stated, to preserve the 

 product, but the fact that it increases the profit is probably the greater 

 incentive to its use. 



In the extracts examined under the chemical control of this laboratory 

 no added salt is found, and experience shows that non-salted extracts keep 

 quite as well as those to which large amounts have been added. Since 

 added salt is not necessary to keep extracts from decomposition, the addi- 

 tion of such can only be regarded as an adulteration. 



Konig* states that the mineral salts, especially the potassium-salts, 

 present in the meat-extract are valuable on account of their action on the 

 nervous system. 



Chittendenf finds that the content of potash-salts causes a quicker and 

 stronger heart-beat. 



The acidity 'of meat-extract, determined by using phenolphthalein as 

 indicator, is calculated to lactic acid as a matter of convenience, and for 

 the sake of comparison with other investigators. 



It is recognized that the acidity of meat-extract is due to various con- 

 stituents, but sarcolactic acid is the predominating acid. It has been 

 suggested that a part of the acidity is due to the phosphates present, but 

 it is probable that the principal salt of phosphoric acid is the secondary 

 potassium compound, which is neutral to phenolphthalein. J 



Fat is a detrimental ingredient in a meat-extract, and if present in large 

 amounts indicates an imperfect method of manufacture, and affects the 

 keeping-quality of the extract. 



* " Chemische Zusammensetzung Nahrurgs-und Genussraittel," p. 236. 



t Med. News, 1891, vol. 58, p. 716. 



X Journ. Amer. Chem. Soc, 1908, vol. 30, p. 1563. 



