low conductivity of meat, the temperature at the surface of the can penetrates slowly to the interior and the juices which are extracted from the meat carry with them protein matter in solution which is afterwards precipitated by heat and remains in the liquid as matter coagulated at the temperature of sterilization.
It is seen that parboiling has many advantages. It extracts less of the valuable matter from the meat, it shrinks the meal before packing so that the tins contain more nutrient matter, and it improves the appearance of the meat to the consumer when opened.
Relation of Canned to Fresh Meat.—In the following table is given the number of ounces of canned meat in a number of cans compared with the equivalent amount of fresh beef used in filling them:
No. of Can. Canned Beef, Equivalent to Fresh Beef.
Ounces. Ounces.
1, 29 44.2
2, 29.9 42.6
3, 28.5 38.7
4, 12.6 19
5, 30.5 57
6, 30.6 50.0
Means, 26.9 42.1
It thus appears that a can of 26.9 ounces of beef contains, as an average content, an amount of meat equivalent to 42.1 ounces of fresh beef, and retains practically all of the nutrient value of the larger quantity of fresh beef.
Canned Ham and Bacon.—It seems unnecessary, as a rule, to can ham and bacon properly cured and transported in a suitable manner. There are occasions justifying the use of these products in tropical countries and in other places far remote from the sources of manufacture, and where the preservation of them, by reason of the character of the climate, is difficult.
The proper preparation of these articles, packing in tins and sterilizing, makes it possible to send them to the most distant points and to have them consumed in the most unfavorable climatic conditions. Canned ham, as it is found upon the market, has a higher percentage of fat and a consequently lower percentage of protein than canned beef. The ham is packed closely and the smaller pieces added for the purpose of filling up interstices between the larger pieces of meat and keeping the can full. It is reasonable to infer that the added meat is pork, although very probably it may not always be so.
Composition of Canned Ham and Bacon.—The character of the canned ham and bacon upon the market may be illustrated by the composition of the following samples (these samples were purchased in the open market and are presumably representative of the products as commonly sold in the shops):
