FoodNet

The school kitchen textbook

1915

Page 65 · 2 recipe records on this page

Presented as published in 1915. Historical recipes may not meet modern food-safety standards. Cook from the modern interpretation, not the original instructions.
Milk is the first food for infants and contains all the food stuffs, which we can separate and study each by itself. We should not think of milk only as a beverage, even though it is drunk as such, much as water. Milk is a natural food and can be used without cooking, and in many combinations of cooked food. The food stuffs are not in the right proportion for adults, as the amount of carbohydrates is small, therefore bread or cereal should be eaten with milk. Milk contains water, sugar, salts, fat, and protein in the form of albumin and casein. After it stands a while, the fat separates and rises as cream. This is churned ; the particles of fat adhere and separate from the water and thus butter is formed. The sugar and salts are dissolved in the water of the milk. The casein is dissolved in fresh milk, but when the milk becomes old, and sours, it separates from the watery part and forms a thick mass which we call curd. This curd is made into 119 120 SCHOOL KITCHEN TEXTBOOK cheese. The watery part left after removing the curd is called whey. As milk contains all these substances it is thicker than water, and when we boil it in an open pan it adheres to the pan and burns quickly. The bubbles of water in the milk, as they change into steam, rise rapidly, the albumin hardens and forms a skin-like coating ; as this skin is thick and tena- cious, owing to the other substances in the milk, these bubbles do not break quickly at the surface as clear water bubbles do, but stretch and climb one upon another till they run over the edge of the pan. This skin-coating is not attractive and many persons skim it off, but as it is protein and a valuable part of the milk, it should be saved by stirring the milk while it is heating, then removing the pan when the bubbles appear on the edge, and stirring the milk until cool. This is scalded milk. Milk that is simply to be taken as hot or warm, may be heated in this way, — if you give it constant attention, — a moment's neglect may cause it to boil over or burn on. To avoid the danger of burning on, or when the milk needs longer heating, or at a lower temperature, use a double boiler. When the whole surface is covered with air bubbles, — not steam bubbles, — the milk is hot enough though not actually boiling. The temperature of boiling milk is slightly higher than that of boiling water, and it will not boil over boiling water. Milk which is really boiled has a different flavor from that of scalded milk. The albumin coagulates by heat; the casein coagulates quickly by the addition of an acid, such as lemon juice, vin- egar, or the acid from the stomach of a calf, which is used in the form of rennet. Casein in milk coagulates naturally in the human stomach. The casein coagulates slowly by long- keeping owing to the change of the sugar into lactic acid. Recipe, No. 36. Lemon Whey Scald one cup milk in a double boiler ; add tablespoon lemon juice; cook it until the curd forms, but do not stir it. When the whey has separated, strain out the curd ; add one table- MILK 121 Spoon of sugar, or more if desired, and serve it hot or cold. This dish is especially refreshing for invalids. Recipe, No. 37. Thickened Milk, Rennet Custard, OR Slip Lemon Whey