+280. Albumin cheese.+[127]--In the rennet cheeses, the albumin, which constitutes about 0.7 per cent of the milk, passes off in the whey. This albumin is not curdled by rennet. It is, however, coagulated by heating. The presence of acid hastens such coagulation but does not cause it when used alone. When the whey is heated to about 200° F., the albumin rises and may be skimmed off. In this form it is recovered and used. It may be shaped is hoops under pressure, as Ricotte, an Italian form. This cheese is pressed firmly and dried. Such albumin is frequently prepared as a poultry feed. +281. Mysost, Norwegian whey cheese.+--The whey contains nearly 5 per cent of milk-sugar which can be recovered by boiling. The Norwegian process which produces Mysost consists in raising the whey to the boiling point, skimming off the albumin as it rises, then concentrating the remainder of the whey. As it reaches sufficient concentration, the albumin is thoroughly stirred back into the mass and the mass finally cooled into forms. Mysost is a brown, hard brittle mass consisting principally of caramelized milk-sugar. Analysis shows such percentage composition as follows: water 10 to 20 per cent, protein 10 to 15 per cent, milk-sugar 30 to 55 per cent. Mysost is found in the larger markets of the United States. _Primost_ is an albumin cheese somewhat similar to Ricotte and Mysost. It is made by precipitating the albumin by acid and heat. The main difference is in the firmness of the cheese. This is regulated by drying. +282. Whey butter.+[128]--The loss of a percentage of fat, rarely less than 0.3 per cent and in some cheeses very much greater, has led to the making of whey butter. For this purpose a separator is introduced and all whey is separated daily. The fat recovered in the form of cream is then ripened and churned. Whey butter is not rated as equal to butter made from whole milk but a fair market can usually be found for the product. The recovery of 0.25 per cent fat means two and one-half pounds of fat to 1000 pounds of whey. This will make about three pounds of butter. Whether whey butter shall be made depends on the volume of business, the extra equipment required, the extra help necessary and the market for the product. As a rule, whey butter is economically recoverable only in large factories. It is not considered advisable to attempt to make it unless one has the whey from 10,000 pounds of milk. In some instances, the combination of small cheese factories with one churning plant has proved to be economical. The objection to the making of whey butter is, that it stimulates carelessness on the part of the cheese-maker because he thinks that the fat will be recovered by skimming. He does not realize that the other milk solids are being reduced in the same proportion as the fat, to the great loss in yield of cheese. CHAPTER XVII _CHEESE FACTORY CONSTRUCTION, EQUIPMENT, ORGANIZATION_