Читать книгу Foods and Their Adulteration - Harvey Washington Wiley - Страница 77
Examination of Fat as a Test for Adulterations.
Оглавление—It is evident, from what has already been said, that the character of the fats which are used in the canning of preserved meats is not always the same as that of the meat to which they are added. A careful study has been made in the Bureau of Chemistry of the fats extracted from different canned meats. The chemical and physical characteristics of these fats are given in the following table:
| Source of Fat. | Melting Point. | Chilling Point. | Iodin Number. | Maumené Number. | Degrees Butyro- refracto- meter. |
|---|---|---|---|---|---|
| C.° | C.° | C.° | |||
| Canned roast beef, | 36.5-43.9 | 27.8-37.0 | 36.1-50.6 | 35.6-36.0 | 47.0-55.5 |
| Canned smoked beef, | 37.7-41.8 | 22.0-29.0 | 50.9-57.5 | .. | 51.0-58.5 |
| Canned ham and bacon, | 23.6-30.5 | 17.5-24.0 | 48.5-68.2 | 39.8-43.5 | 49.0-58.2 |
| Fowl, | 28.0-34.0 | 12.0-36.5 | 67.0-86.4 | 38.9-52.0 | 49.0-62.5 |
It has been noticed that the crystals deposited by the evaporation of the ether solution of chicken fat resemble beef stearin in shape, but are much smaller and more delicate. It is seen that the melting point of fat in ham and bacon is rather lower than in leaf lard. It is evident, therefore, that this fat is not lard or, at least, not wholly composed of the best lard, but probably consists of the fat not usually employed for lard making.
