In addition to the above nutritive elements there are also a series of extractive substances to which is due the pleasant taste of the meat. When such food is boiled these substances and salts pass into the water, and such meat loses in flavor, though not in its nutritive qualities, for the water i.e., the soup is not nutrimental at all. Meat, if prepared for the table directly after the animal is killed, would not be palatable; and it is, therefore, necessary for it be kept for a given time before it is eaten. Dr. Wiley, of Washington, considers that meat improves if kept not exceeding fourteen days in cold storage, after which time it begins to lose its best qualities. When meat is chilled it does not lose its pleasant taste; but when it is frozen the case is very different, for then it loses its beneficial juices, which escape into the surrounding ice. In such meats, therefore, the extractives which give the pleasant flavor are wanting. Refrigerated meat generally arrives in Europe in excellent condition from America. Before animals are slaughtered to be used for food a rigorous examination by veterinarians must be made, in order to avoid poisoning from meat in a condition of putrefaction, or from diseased animals. Some animals, such as pigs, very often suffer from acute inflammatory diseases caused by catching cold while on long journeys prior to being slaughtered. Fortunately, in the early stages of such illness there is little danger, for it can be avoided by thorough bleeding. The Jewish method of bleeding an animal is thus particularly to be recommended, for by this means poisonous products can leave the animals’ bodies in large quantities. Meat retaining all the natural blood decomposes very rapidly, especially in hot climates, and we must not forget that such poisonous substances, as ptomaines, in meat, are not destroyed by the process of cooking. The greatest danger from poisoning lies in oysters, which are otherwise a most digestible food. This is owing to the frequent presence of sewage contamination in the waters where they are bred, thereby causing veritable epidemics of typhoid fever. Just as in fish foods, oysters and mussels, sausages in the meat foods are the most frequent cause of poisoning when they are not quite fresh and thoroughly sound, and from such a cause epidemics from poisoning are frequent in Germany. Sausages are a very nutritious food, as they contain a large amount of fat; their greater value when made from the blood of pigs, on account of its richness in iron, will be specially dealt with in another chapter. Fish contain somewhat less albumin and much more water than meat, but some of them are rich in fat, such as the eel. We show in the following table the nutritive values in each 100 parts of some of the most frequently eaten fish:—