239. Conditions affecting the rate of cheese ripening.—The rate at which these agents cause ripening of the cheese depends on several factors.[118] Most of these factors are within the control of man. They are as follows: the length of time; temperature of the curing-room; moisture-content of the cheese; size of the cheese; the quantity of salt used; the amount of rennet; the influence of acid.
240. The length of time.—The water-soluble nitrogen compounds increase as the cheese ages, other conditions being uniform. The rate of increase is not uniform; it is much more rapid in the early than in the succeeding stages of ripening.
241. The temperature of the curing-room.—Very few cheese factories have made any provision for regulating the temperature of the curing-room. Without such provision the temperature follows closely that of the outside air. In some cases the curing-room is located over the boiler-room and hence becomes very hot. In the cheese warehouses, provision has been made to control the temperature very closely. Experiments show that the soluble nitrogen compounds increase, on the average, closely in proportion to an increase of temperature, when the other conditions are uniform.
The temperature of the curing-room has a material effect on the quality of the cheese. Cheese made from the same day's milk, and part cured at 40° F., part at 50° F., part at 60° F. show considerable differences, the greatest seeming to be in the flavor and texture. Those kept at the low temperature cure more slowly and develop a milder flavor, those at the higher temperature cure faster and develop undesirable flavors. At the higher temperature the undesirable organisms seem to be more active. Some very skillful makers and judges of cheese have always contended that if Cheddar is properly made, firmed to the body and texture of a high-class cheese, ripening at 55 to 60° F. gives a higher quality. Such a cheese must be low in moisture, perhaps 3 to 5 per cent lower than one cured successfully by the cold process.
The following tables[119] XVII, XVIII show the effect of different temperatures of curing cheese on the total score and on the points of the flavor, body and texture:
TABLE XVII
| Table Showing the Relation of Temperature of Curingto Total Scores | |
| Time of Plating | Cheese Number |
40° | 95.7 |
| 50° | 94,2 |
| 60° | 91.7 |
TABLE XVIII
Table Showing the Relation of Temperature of Curingto Score of Body and Texture, and Flavor | |||
| Temperature of Curing | 40° F. | 50° F. | 60° F. |
Body and texture | 23.4 | 32.0 | 22.2 |
| Flavor | 47.4 | 46.4 | 44.8 |