—The examination made of numerous samples of canned meat in the Bureau of Chemistry shows that the adulteration of these foods is rather common but by no means general.
Canned Horse Meat.
—Horse meat is commonly used for human food in many European countries, although it is believed that it is not used to any extent in the United States. When procured from healthy animals in a proper way there is no hygienic objection to its use, though it is considered to be somewhat tougher than the flesh of other animals more commonly employed as food, but that is probably due to the fact that horses are not raised for food purposes and are usually not used for such until they are worn out in domestic service. There are many sentimental and often religious objections to the use of horse meat, but experience has shown that it is wholesome and nutritious. Horse meat is characteristic in containing more natural sugar, commonly known as glycogen, than any of the other ordinary meats used for human consumption. It approaches in its content of sugar some of the shell-fish flesh, such as that of the lobster. Practically all of the horse meat which is prepared in this country is exported to Europe. There are cases, however, on record of the sale of horse flesh to domestic consumers. Especially could it be used in this way in the form of sausage or other finely comminuted products without much danger of detection.
Composition of Horse Meat.
—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.