—The names applied to the different kinds of lard may be referred principally to the parts of fat used, such as leaf lard, intestinal lard, etc., or to the method of preparing it. The old-fashioned method of preparing lard for family use consisted in placing the fat in an open kettle and heating usually over the open fire. The rendering takes place as the mass increases in temperature, so that the residual tissues become browned by the high temperature reached. Lard made in this way is of most excellent quality and, of course, being made under family supervision, its character is well understood and the parts of the body used are well known. In the large packing establishments the lard is usually rendered by the application of heat in the form of steam under pressure, of a suitable temperature to make the character of lard uniform. Large yields can be secured in this way with less charring of the residual tissues, and consequently a finer and whiter color in the lard itself. Lard of this kind is sometimes known as steam rendered lard.
Uses of Lard.
—The fat of swine prepared as above mentioned, and known as lard, finds a very extended use in every kitchen. It is mixed with various forms of bread making materials, cake, etc., and is often known in this sense as “shortening.” It is also employed for lubricating the pans and other culinary utensils used for baking purposes. It is sometimes employed for the purpose of cooking by the process of frying or of introducing the substance to be cooked directly into the hot lard, as in the frying of oysters, the making of doughnuts, and similar operations. Lard has come to be looked upon as a necessity in every kitchen, even of the humblest citizen.
Many objections are made to the use of lard on hygienic grounds, and probably on account of its cheapness and general utility it is more freely used in American cooking than it should be. In other words, American cooking is under the reproach of being too greasy. There is no reason to question the digestive and nutritive value of lard when used in proper quantities and in proper conditions. It is a typical fat food composed of materials which are almost wholly oxidized in the body and which upon combustion produce a higher number of units of heat than that of any other class of food substances.
COMPOSITION OF DIFFERENT VARIETIES OF AMERICAN LARD.
| Specific Gravity. | Saponi- fication Equiv- alent. | Melting Point. | Melting Point of Fatty Acid. | Crystal- lizing Point of Fatty Acid. | Rise of Temper- ature with Sulfuric Acid. | Iodin Ab- sorbed. | Water. | |
|---|---|---|---|---|---|---|---|---|
| C.° | C.° | C.° | C.° | Percent | Percent | |||
| Leaf lard, | .9057 | 272.64 | 41.6 | 43.0 | 40.40 | 39.7 | 59.60 | .165 |
| Pure leaf lard, | .9028 | 281.01 | 44.9 | 42.8 | 40.40 | 37.1 | 53.04 | .025 |
| Prime steam lard, | .9052 | 279.06 | 38.4 | 41.8 | 39.53 | 33.7 | 63.84 | .040 |
Adulteration of Lard.
—The principal adulteration to which lard is subjected is admixture with other and cheaper fats. Among the fats which are used for this purpose may be mentioned beef fat and cottonseed oil. Beef fat has a higher melting point than lard and cottonseed oil a much lower melting point, being liquid at ordinary temperatures. A mixture of beef fat and cottonseed oil may, therefore, be made, having approximately the same melting point as lard itself. The addition of this mixture to lard would not alter its melting point to any sensible extent. Instead of using the whole cottonseed oil for the purpose mentioned it may be previously chilled and its product of a higher melting point, or as it is sometimes called, the stearin of cottonseed oil, may be used for admixture with lard. Large quantities of these mixed fats were formerly made in this country under the name of “compound lard” in which the above adulterants were the chief constituents. The laws of the various states are happily of a character which forbids the sale of a mixture of a compound of lard and other fats under the name of lard, although there is no objection to such admixture from a hygienic and dietetic point of view. There are many hygienists who are of the opinion that the more extended use of vegetable oils instead of lard would be of value to the health of the public. If this be true, the admixture of a vegetable oil with lard would improve it from a hygienic standpoint. The principal, perhaps the sole, objection to such admixtures is their fraudulent character. Vegetable oils, especially cottonseed oil, being very much cheaper than lard, their use in lard without notification cheapens the product and defrauds the customer. Lard may also be adulterated with its own stearin. In the manufacture of lard oil a residue is left of a much higher melting point and this residue may be mixed with a vegetable oil, such as cottonseed, in the production of a compound of approximately the same melting point as lard itself. In a case of this kind both constituents are fraudulent, in as much as neither the cottonseed oil nor the lard stearin may be regarded in any sense as lard.
Detection of Adulterations.
—The presence of cottonseed oil in any form in lard is at once determined by the application of a simple color test known as the Halphen test. This is not a reliable test in those cases where the animal has been fed cottonseed.