The ingredients commonly employed for modified milk are (1) cream containing 16 percent of fat; (2) centrifugally skimmed milk by which the fat has been removed; (3) milk sugar or a standard solution of milk sugar of say 20 percent strength; and (4) lime water.
Formulæ.—It is obviously impossible to establish formulæ universally applicable even to healthy infants, but the following may be regarded as typical, representing the composition of a modified milk, to suit the needs of an average growing infant during its first year:
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Period. | Fat. | Proteids. | Sugar.
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| Percent. | Percent. | Percent.
3 to 14 days, | 2 | 0.6 | 6
2 to 6 weeks, | 2.5 | 0.6 | 6
6 to 11 weeks, | 3 | 1.0 | 6
11 weeks to 5 months, | 3.5 | 1.5 | 7
5 to 9 months, | 4 | 2 | 7
9 to 12 months, | 4.5 | 2.5 | 3.5
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(Albert E. Leach, "Food Inspection and Analysis.")
Solid Infant's Food.—A large number of infant foods in the solid state are upon the market. These have been studied very carefully by many observers with a view not only of determining their chemical properties but also their relative digestibility. These prepared infant foods are not always made in harmony with the natural demands of young children. As has just been indicated, they are not, as a rule, suitable for infants before the time of weaning, being better adapted to the use of young children. In the following tables are the data representing the chemical composition of some of the common infants' foods.
Invalid Foods.—The term "invalid foods" is applied to almost every kind of a concoction containing a food substance which is administered to an invalid or convalescent, often for medical purposes rather than for real nutrition. Chief among these invalid foods may be mentioned the meat extracts containing that portion of the meat soluble in hot water. These bodies consist chiefly of meat bases together with certain soluble salts and it has long been recognized that they have very little nutritive value. They are also found in concentrated or even a dry state. The unconcentrated invalid foods of this class sometimes contain glycerol (glycerine) or alcohol as a preservative. There are also many forms of meat juice supposed to be the direct extract by pressure or otherwise of the natural juice of the meat. Since these bodies could not be preserved otherwise than by sterilization, which would coagulate the albuminous portion, they are often preserved by the addition of glycerine or some other antiseptic substance. It is doubtful
