The surface of the cheese should be watched to see that the cloths stick. If they do not, the surface will crack, due to the evaporation of the moisture. If the cloths are loosened, they should be removed and the surface of the cheese greased with butter. The grease will tend to prevent the rind from cracking. If the surface of the cheese is not smooth, due to wrinkles in the bandage, or if it cracks, due to the lack of cloths, it furnishes the opportunity for insects to lay their eggs and the larvæ to develop within the cheese. Molds also lodge and grow in such cracks. [Illustration: FIG. 53.--Cheddar cheese curing-room.] The cheese should be kept clean while in the curing-room. This means that the hands of the person handling the cheese must be clean. The shelves should be washed with good cleaning solution and scalded with hot water whenever they become greasy or moldy. Some means should be provided for regulating the temperature and humidity of the curing-room. In most factories this is accomplished by opening the doors and windows at night to admit the cool air and closing them in the morning to keep out the hot air. Care should be taken to keep the doors and windows closely secured. The windows should have shades to keep out the sun. If the room becomes too dry, the floor may be dampened with cold water. The length of time in the curing-room depends on how often shipment is made to some central warehouse or to the market. This usually varies from two to six weeks. When the surface of the cheese becomes dry and the rind is well formed, the cheese may be paraffined. It usually requires four to six days after cheeses are taken from the hoop before they are ready for this process. The object of paraffining is to prevent the escape of moisture and to keep the cheese from molding. +248. Evaporation of moisture from the cheese during ripening.+--The losses due to evaporation while the cheeses are curing are a considerable item. The rate of evaporation depends on the temperature and humidity of the curing-room, the size of the cheese, the moisture-content and protection to the surface. Table XIX[120] shows the effect of size of cheese and temperature of the curing-room, on losses while curing. This table shows that the evaporation of moisture is more as the size of the cheese decreases and the temperature is increased. This is probably due to the fact that the smaller cheese has more surface to a pound than a large cheese. The evaporation increases with temperature, probably because of lowered relative humidity. The humidity can be tested with an hygrometer. TABLE XIX SHOWING THE VARIATION OF LOSSES IN WEIGHT OF CHEDDAR CHEESE WHILE CURING, DUE TO SIZE OF CHEESE AND TEMPERATURE OF CURING-ROOM