38 BULLETIN 608. U. S. DEPARTMENT OF AGRICULTURE 
by the Trappists, very successful imitations are made outside the monasteries 
In that region. 
Either whole or partly skimmed and preferably slightly acid milk is heated 
to 90° or 95° F., and sufficient rennet added in order to obtain the desired firmness 
of the curd in about 30 minutes. Coloring matter is usually added to the milk. 
The curd is cut very fine and in a manner similar to that followed in making Em- 
menthaler cheese. This requires about 20 minutes, after which part of the whey 
may be removed. The curd is then stirred and may be heated or cooked to a 
moderate degree. The final temperature reached in cooking varies from 100° 
to 105° F.. depending upon the acidity of the milk. The time required in stirring 
and heating is about 20 minutes. The curd is then allowed to settle and the whey 
removed. After being stirred vigorously for from 2 to 4 minutes, the curd is put 
into molds which are of two sizes, the smaller about 7 inches in diameter and the 
larger about 10 inches. A disk is placed on the cheese and pressure applied by 
means of presses for from 10 to 12 hours, the cheese being turned and the cloths 
frequently changed during that time. The next day the hoops are removed and 
the cheese salted. After drying for about 24 hours it is transferred to tne ripen- 
ing cellar, where it remains from 5 to 6 weeks. In this place a temperature of 
about 55° F. and a relative humidity of 85 or 90 per cent are preferred. During 
ripening the cheeses are turned very frequently and washed with salt water, the 
frequency depending somewhat upon the rapidity with which molds develop. 
The cheese is often sold before the ripening process is entirely complete. 
POTATO 
This cheese is made in Thuringia, in the central part of Germany. In the 
manufacture of potato cheese, curd is made from sour milk of cows, or in some 
cases from milk to which rennet has been added. Sometimes sheep's or goats' 
milk is used. The potatoes are boiled and grated or mashed. One part of the 
potatoes is thoroughly mixed or kneaded with two or three parts of the curd. 
In the better cheese three parts of potatoes are mixed with two of curd. During 
the mixing salt and sometimes caraway seed are added. The cheese is allowed to 
stand for from two to four days while a fermentation takes place. After this the 
curd is again thoroughly kneaded and placed in forms for a day. It is then dried 
and is sometimes covered with beer or cream and is finally placed in tubs and 
allowed to ripen for 14 days. 
A variety of this cheese is made in the United States. It is probable, how- 
ever, that it is not allowed to ripen for quite so long a period as the potato cheese 
of Europe. In all other essentials it appears to be the same. 
POTTED 
This cheese very probably originated in the United States. It is usually 
prepared from well-ripened Cheddar cheese by grinding it very fine and mixing 
with butter, condiments, spirits, etc. In the past it has been put up in small 
porcelain jars, but at the present time a portion of it is wrapped in waxed paper 
and either tin or lead foil and is often known as Club cheese. 
PRATTIGAL 
This is made from skim milk of cows, and is so named from the valley of 
Switzerland in which it is made. Its manufacture is the same as that of Lim- 
burg. Cheeses weigh from 20 to 25 pounds each. 
PRESTOST 
Prestost is a product of Sweden, where it is often called Saaland Pfarr. It 
is a rennet cheese made from the fresh milk of cows, and resembles Gouda. It 
was known in the eighteenth century. The milk is set at 90° F. and is allowed to 
become very firm, when it is cut coarse with a wooden knife and poured into 
a sieve, which allows the whey to drain off. The curd is then put into a cloth 
and kneaded. Whisky is mixed with the curd, which is then packed in a basket, 
and after some salt is sprinkled on the surface it is put into a cellar. The cloth 
inclosing the cheese is changed daily for three days, after which the cheese is 
washed with whisky. A cheese is cylindrical in shape and weighs from 5 to 30 
pound*. 
