Читать книгу Foods and Their Adulteration - Harvey Washington Wiley - Страница 95

—A number of samples of horse meat of undoubted origin and wholesomeness have been examined in the Bureau of Chemistry and the data tabulated. The average composition of sixteen samples of horse meat, representing different parts of the carcass, is shown in the following table:

Water,	69.81	percent
Water in fat-free substance,	76.91	„
Fat,	9.61	„
Protein,	19.47	„
Protein insoluble in water,	14.83	„
Gelatinous protein,	1.23	„
Meat bases,	1.70	„
Glycogen,	1.82	„
Ash,	1.01	„

Composition of Dry Material—

Protein,	67.98	percent
Fat,	27.71	„
Ash,	3.18	„
Undetermined,	1.13	„

The high percentage of glycogen in horse meat is one of the safest methods of determining its character when comminuted or cut up into pieces so small as not to be identified by the usual anatomical characteristics. Very few other kinds of edible flesh contain as much as one percent of glycogen. Glycogen is a transitory product which tends naturally to be broken up into other substances, and, hence, even in horse meat after slaughter, it may rapidly disappear and thus, unless the meat is examined at once, very little glycogen may be found in it. A safer test for horse meat is in the nature of the fat therein. This fat does not tend to change as the glycogen does, and, therefore, in a pure preparation of horse meat even in a finely comminuted state the separation and examination of the fat will lead to a determination of the character of meat employed. The fats of horse meat have a lower melting point, a higher iodin number, and a higher heat value when mixed with sulfuric acid than those of beef.

Indeed, these differences are so marked as to afford a ready means of detection to the practical chemist. Even in the mixture of horse meat with other meat the variation in the character of the fats will be such as to lead to a correct judgment respecting the approximate amount of horse meat which has been used, provided it forms any notable amount of the mixture.