FoodNet

Experimental cookery

1932

Page 256

Presented as published in 1932. Historical recipes may not meet modern food-safety standards. Cook from the modern interpretation, not the original instructions.
Processed cheese. Rogers states that before the development of the can in which Cheddar cheese may be ripened, the "only commercial method for putting Cheddar cheese into a more attractive and convenient form is the one known as processing. After the rind is removed, the cheese is ground, a small quantity of water and an emulsifier, usually sodium citrate, are added, and the mass is heated with constant stirring until it becomes fluid. The emulsion is run into forms, which in many cases are boxes lined with tinfoil, in which it is sold. The cheese hardens quickly and, as the wrapping adheres closely, there is no trouble from molds. Moreover, as the temperature is high enough to constitute pasteurization, most of the bacteria are killed and the enzymes destroyed, so that ripening is stopped. In this process, much of the original character of the cheese is lost; but, in spite of this objection, the advantage of the package is so great that a large part, possibly one-third, of all the cheese made in the United States is sold in this form." Templeton and Sommer have investigated various salts that may be used as emulsifiers in processed cheese. They state the purpose of the salt is to I 314 MILK AND CHEESE prevent separation of the fat from the cheese and at the same time give the finished product the desired body and texture. They quote Habicht as stating that an alkaline monovalent cation combined with a polyvalent anion, such as sodium citrate, is the ideal emulsifying salt. The physico- chemical explanation is as follows: There is partial saponification between the cation (sodium, if sodium citrate is used) and the fatty acids. The soaps formed are good emulsifiers. In addition the anion, which is a solvent for casein, combines with the casein of cheese so that a film of casein surrounds each fat globule, thus emulsifying it and preventing its escape from the mass. Later we find that the citrate ion is also a good peptizer of egg and flour proteins. Loaf cheese. Rogers states that blending is used extensively for Cheddar and Swiss cheese. In this process the cheese is ground and heated in steam-jacketed kettles, 60° to 70°, and then poured into molds. In the initial heating separation of the fat occurs; but with longer heating the casein becomes plastic and stringy and encloses the fat. Further agitation causes the mass to lose its plasticity and become the consistency of heavy cream. At this time it is poured into the molds. The plasticity of the cheese is an important part of the process. Once the plasticity is broken it is almost impossible to restore it. The method of manufacture, the degree of ripening, the acidity of the cheese, and possibly other factors influence the degree of plasticity attainable in the heated cheese and the length of time the mass will remain plastic. Sodium and ammonia seem important in the emulsification of the product.