The book of cheese

The factories are variously built. A common type takes advantage of sloping ground so that the floor at one end may be on the ground level and run backward into a hillside until the other end is a cellar with small windows at the ceiling opening at the ground level (Fig. 23). The family of the cheese-maker often lives in the same building above the factory.

160. Making the cheese.—Limburger cheese is made from the whole milk. When the milk is received at the factory, it is placed in the cheese vat. As the milk is delivered both morning and evening without cooling, it reaches the factory at a temperature of 90 to 96° F. In some cases the night's and morning's milk is mixed and then warmed to about 94° F. This practice is not recommended but is frequently adopted, when the supply of milk becomes too small to work in two lots. As soon as all of the milk has been delivered, the cheese-making process begins. No starter is used. The milk is not ripened because no acid development during the making process is desired. The milk is set or curdled at the temperature at which it is received at the factory, usually from 90 to 96° F. Sufficient rennet extract is used to give a firm coagulation in twenty to thirty minutes. This usually requires 2½ to 3 ounces of rennet extract for each 1000 pounds of milk: This is diluted in about forty times its own volume of cold water and added to the milk. (For method of adding rennet extract to milk, see Chapter V.) When the coagulum has become firm so that it will split clean over the finger, the curd is ready to cut. Coarse Cheddar cheese knives are used. Sometimes only the perpendicular knife is employed, and the curd is broken up while being stirred with the hands and rake. This usually causes a large fat loss. After cutting, the curd is stirred first by hand and later with an ordinary wooden hay rake. Usually the curd is not "cooked" or heated after setting, though occasionally it is brought up as high as 96° F. to 98° F. If the curd does not firm up, the temperature may be raised to 98° to 100° F. to aid in expelling the moisture.

When ready to dip, the curd should still be in large soft shiny pieces. It requires from one hour to an hour and thirty minutes from the time the rennet extract is added until the curd is ready to dip. When, in the judgment of the cheese-maker, the curd has become sufficiently firmed in the whey, the whey is drawn down to the surface of the curd. The curd is then dipped into the Limburger molds. These molds are 5 inches square by 8 inches deep without top or bottom. Usually there are five or six of these molds built together into a section. These molds are placed on a draining table beside the vat and the curd is ladled into them with a large tin ladle. The draining table has strips on both sides and one end and slants toward the other end so that the whey will drain from the curd and yet not go on the floor except at the one end. This makes it easy to save and catch the whey for stock feed.

161. Draining and salting Limburger.—In some factories, a clean piece of burlap is put on the draining table and the molds and curd placed on the burlap. This aids in the rapid draining of the whey from the curd and prevents the loss of curd particles. The curd should be turned frequently in the mold to obtain uniform draining. The molds are transferred to the salting room as soon as well drained, usually in about twelve hours, but sometimes they are left until the following morning. Here they are placed on another draining table, which has strips about 5 inches high on the sides and one end. The cheeses are placed along this board, each cheese being separated by a piece of board 4 inches high and 5 inches wide. When the row is filled, a long strip the length of the table is placed against the row. Another row is laid down against this strip in the same manner as the first, and so on until several rows are on the table. The last long strip is held firmly in place by sticks wedged between it and the opposite side of the table. These strips and pieces form a mold for each cheese while draining. Usually the cheeses are turned several times in this period to obtain a uniform expulsion of whey. In about twenty-four hours the cheeses are ready to be salted. This is done by applying the salt to the outside of the cheese. The edges are rolled in a box of salt and the salt then rubbed on the two broad surfaces. Any excess salt is brushed from the cheese with the hand. The cheeses are then laid on a draining table in single layers. The second day, they are salted again in the same way and piled two deep; they are salted again the third day and piled three or four layers deep. The salting room or cellar should have a temperature of 60° F. and be fairly damp. The amount of salt used is very important. The tendency is to use too much salt. This retards the ripening process and in extreme cases gives the cheese a salty taste. If not enough salt is used, the cheese will deteriorate very rapidly on account of the development of undesirable types of fermentation. The cheeses when salted are then placed in the curing room, which is a cellar, usually beyond the salting room. This cellar should have a temperature of 58° to 64° F. and a relative humidity of 95 per cent of saturation. In winter it is necessary to have a fire to keep the rooms warm, otherwise the cheese would cure very slowly or not at all. In some factories the curing and salting cellars are a single room.

162. Ripening Limburger.—When first placed in the curing cellar, the cheeses are put on edge close together, and as they cure are gradually separated. While in the curing cellar, the cheese must be rubbed frequently by hand and washed, usually with salt water. The object of the rubbing is to keep the surface of the cheese moist and prevent the growth of molds. The drier the cheese and the more mold, the oftener the cheeses must be rubbed. The drying or the evaporation from the cheese can be retarded by sprinkling the floor of the cellar with water. When first placed in the curing cellar, they are usually rubbed daily; after a few days they are rubbed every other day and finally as often as the cheese-maker can find time to work at them. The more the cheeses are rubbed, the better the rind.

In the curing of Limburger cheese, protein compounds are attacked by the micro-organisms. Certain highly-flavored fatty acids are commonly produced.61 This change works most rapidly near the outside and more slowly toward the center of the cheese. The stage of ripening can be determined by examining the cheese. When first made, a cheese is harsh and hard and the outside is more or less white: as the curing changes take place, the cheese becomes soft and pasty or buttery. The outside color changes from a whitish to a yellowish and finally even a reddish brown. It requires considerable time for the ripening agents to work from the outside to the center of the cheese. As ripening progresses, Limburger cheeses tend to become soft enough to break in handling. If such cheeses are wrapped in manila paper after three to four weeks of ripening and packed in boxes, losses from handling are eliminated. One loose board is left on each box and the boxes remain in the ripening cellar until the cheese-maker decides by removal and examination of cheeses from time to time that they are ready for shipment. When fully ripe, the cheese spoils very quickly. Unless handled very carefully, the outer part may actually rot before the interior is fully ripe. The cheeses are shipped from the factory when they are eight to ten weeks old. They are then placed in cold storage, which checks the action of the ripening agents and so lengthens the commercial life of the cheese.

163. Marketing and qualities of Limburger.—As shipped from the factory, each cheese is wrapped in heavy manila paper and frequently also in tin-foil. The cheeses are packed in boxes which hold forty-eight. Each cheese weighs about two pounds.

The cheese should contain the proper amount of salt. The most common defect is in the flavor. If the milk is not free from bad odors and flavors, these are apt to be more pronounced in the cheese than in the milk. (For care of milk see Chapter II.) Gas-forming fermentations are very bad in this variety of cheese as they cannot be controlled and give the cheese a bad flavor and a "gassy body." When a cheese is gassy, the sides are most liable to be bulged and the body is full of gas holes or pockets. Another defect is a sour cheese. This is caused by the development of too much acid in the milk or during the manufacturing process. A sour cheese usually cures slowly and has a pronounced sour taste. The body is hard and bitter.

If the cheese contains too much moisture, it will cure rapidly and the body will be very soft and pasty. In extreme cases it will be so soft that it will run when the rind is broken. On the other hand if the cheese does not contain sufficient moisture, it will cure very slowly and the body will be hard and dry and sometimes crumbly. There is no standard score-card for judging Limburger cheese. The Wisconsin Cheese-makers Association62 uses the following score-card for Limburger:

164. Yield and composition of Limburger.—The yield of cheese depends on: (1) the amount of fat and other solids in the milk from which it is made; (2) the amount of moisture incorporated into cheese; (3) the loss of solids during the manufacturing process.

The yield varies from 12 to 14 pounds of cheese from 100 pounds of milk. The more fat and other solids in the milk, the more cheese can be made from 100 pounds of the milk. The more moisture incorporated into the cheese, the larger the yield. The quality of the cheese and the amount of solids determine the amount of moisture that can be incorporated into the cheese. The greater the losses during the manufacturing process, the less is the yield. The composition of Limburger cheese is affected by the same factors as the yield. The average cheese probably carries from 40 to 42 per cent of moisture. Limburger cheeses will vary in composition from this analysis about as follows: water 38 to 44 percent, protein 21 to 25 percent, fat 25 to 30 percent. The differences in practice in factory groups are considerable. Certain markets call for more solid brands, others for the very soft forms.

165. Münster cheese originated in Germany near the city whose name it bears. There is a limited demand for this variety in America; therefore it is not extensively made. It is usually manufactured from whole milk in a Limburger or Brick cheese factory. The process of manufacture is between that of these two varieties in temperatures used, firmness of curd and amount of moisture in the curd and cheese. The process is probably more like that of Limburger. The curd is firmed more in the whey than for Limburger, and more acid is developed. The cheeses are pressed or drained in round forms 7 inches in diameter and 6 inches high. The hoops are lined with cloth to prevent the loss of curd particles while draining. When the cheeses are sufficiently drained, until they are firm enough to hold their shape, the cloths are removed. The cheese is salted by rubbing dry salt on the surface or soaking the cheese in brine. The product is handled in the curing room very much the same as Limburger or Brick cheese. When sufficiently ripe, each cheese is wrapped in parchment paper and placed in a separate wooden box. This cheese, when cured, has a characteristic flavor which is between that of Limburger and Brick. The body is more or less open. The essential factor in the manufacture of Münster cheese is clean milk. Bad fermentations, such as produce gas and bad flavors, seriously interfere with the manufacture and sale of the product. The cheese is usually made in the late fall and winter, when it is difficult to manufacture Limburger.

CHAPTER X

SEMI-HARD CHEESES

Between the quickly perishable soft cheeses and the typical hard group, are two series of varieties, one ripened by green mold and best known by Roquefort, the other ripened by bacteria and typified by Brick cheese. These cheeses are fairly firm, hold their shape well, ripen over a period varying from a few weeks to several months and their marketable period is comparatively long. In texture they are intermediate between the conditions known as "soft" and "hard." In water-content, they range at their best from 37 to 45 percent. Outside these limits, the cheeses are often marketable but they lose in quality63 and trueness to type.

166. The green mold group.—There are three well-known semi-hard cheeses ripened by green or blue-green mold.64 The mold is an incidental factor in certain other forms but none of these forms has won larger than local or purely national recognition. French Roquefort, on the contrary, is probably the most widely known of all cheeses. Stilton, to a small degree at least, has followed the English to the many lands they inhabit. Gorgonzola, although made in Italy alone, has a large market in other parts of Europe and in America. In the manipulations of manufacture, these forms are not closely related but they resemble each other in that each becomes streaked or marbled by the growth of green mold (Penicillium Roqueforti) through open spaces within the cheese. The "blue-veined" or marbled cheeses have a characteristic taste which is developed in its most typical form in Roquefort.

167.—This is a rennet cheese made from sheep's milk (with occasional and minor admixture of goat's and cow's milk) in the section of southern France centering about Roquefort in Aveyron. The practices are standardized and controlled by a few companies, thus reaching exceptional uniformity. Roquefort is uncolored, open, made from firm but brittle or crumbly, not tough or waxy curd. Each cheese is about 7¼ inches (20 cm.) in diameter and 3¼ inches (9 cm.) in thickness without a definite rind, and when ripe enough for market is scraped carefully, closely covered with tin-foil and kept in refrigerators. The cut cheese shows extensive open spaces which are lined with green mold. This cheese, in addition to a strong cheesy odor and taste, has a peppery or burning quality which according to Currie65 is due to the formation of volatile fatty acids such as caproic, caprylic and capric from the butter-fat of the sheep's milk used. A series for Roquefort cheeses selected for excellent quality was found by Dox66 to show the following composition:

TABLE IV

The composition of the sheep's milk of the Roquefort producing region is reported by Marre:67

TABLE V

The cheeses when properly made in the local factories are transported to Roquefort for ripening in the famous caves which have made possible the development of a great industry.

The Roquefort caves were originally natural openings leading back into the face of a cliff until they reached a deep, narrow fault or crack in the rock leading to the plains above. The cooler air from the plains came down this crack over moist and dripping rocks and issued through these clefts in a cold moisture-laden current which kept the caves about 50 to 55° F. and moist enough to ripen the cheeses without shrinkage. As the business outgrew the natural caves, great cellars, some of them five or six floors deep, were excavated and tunnels were dug back to the crack so that the strong ventilating current reaches every part of the cellars and keeps both temperature and relative humidity favorable to the ripening of the cheeses.

168. Cow's milk or Façons Roquefort.—The supply of Roquefort is automatically limited by the supply of sheep's milk. The sheep gives milk only about five months in the year and at best a scant average of about a pint a day to a sheep. Sheep's milk for cheese-making is not produced, therefore, outside of very limited regions. Some cow's and goat's milk unavoidably finds its way regularly into the industry itself. Attempts were naturally made to substitute cow's milk. Outside the controlled area, factories were established for this purpose. The quality of the product did not equal that of the Roquefort factories, and French courts decreed that the name Roquefort should not be used for such products. Although some local success was obtained, not much progress was made against the intrenched Roquefort industry. Similar attempts to make such a product in Germany68 were tried on an extensive scale but failed. More recently, under the inspiration of Conn, the United States Department of Agriculture and the Storrs Experiment Station have studied the possibilities of such an industry. Although the work is not completed, the preliminary reports69 have indicated the fundamental principles which must underlie such development.

169. Outline of making Roquefort.—Some of the results of these experiments are summarized in the following paragraphs:

Curdling time.—One and one-half to two hours gave most satisfactory results in forming curd. This should be very firm and stand until it begins to "sweat," until beads of whey have begun to collect upon its surface.

Cutting.—The cow's milk curd gave best results when cut in two directions with the half-inch curd knife. The resulting columns, a half inch square in cross-section, may be handled without excessive losses.

Draining.—The cut curd is dipped to a draining rack covered with cloth with as little breaking as possible. During the draining process, a certain amount of turning is necessary to facilitate the separation and escape of the whey. If handled too much, losses of fat are increased and the curd becomes tough or waxy instead of remaining brittle or crumbly. When properly handled, not over 0.35 per cent of fat is lost. Under favorable conditions, four-ninths to two-thirds of the original weight of curd will separate and run off as whey in twenty to thirty minutes. The curd meanwhile is exposed to the air of the room and cools toward room temperature. If cooling goes too far, further drainage is interfered with. Hence the curd is put into the hoop and the drainage completed while the cheese is reaching its final form.

Hoop.—Hoops for cow's milk Roquefort must be 7½ inches in diameter and about 5¾ inches high to hold curd enough to produce a cheese the size of the standard Roquefort when completely drained. Sheep's milk with its higher percentage of solids does not require such high hoops. The curd as it goes into the hoop should be a soft, pulpy mass with no suggestion of toughness.

Inoculation with mold.—The mold for Roquefort cheese (Penicillium Roqueforti70) is readily grown in pure culture in ordinary loaves of bread. For this purpose loaves hot from the oven are quickly drenched with or immersed in hot paraffine to form an impervious crust to retain moisture as well as to keep out contaminations. It is then allowed to cool. The interior of each loaf is inoculated by drawing a suspension of P. Roqueforti spores in water into a sterile pipette (10 c.c.) which is then thrust through the paraffined crust to the center of the loaf of bread and allowed to empty there. The hole is sealed up with paraffine. These loaves are incubated for about a month at room temperature. When cut, every open space should be found lined with the green spores of the mold. When dry enough, the mass may be powdered, and put into an ordinary pepper box. When the curd is ready to go into the hoop, this mold powder is sprinkled upon it from the pepper box.

Handling.—Freshly made cheeses are turned within the first hour to insure the proper smoothness of both sides. Further draining is best accomplished in a room at about 64° F. with a relative humidity of 85 to 90 per cent. If the surface of the cheese becomes too dry, a rind is formed. No real rind is permitted on Roquefort. If the temperature is too high, slime forms quickly and unfavorable fermentation may occur. Slime (bacteria and Oidium lactis usually) must be scraped when it becomes too heavy.

Salting.71—Experimental cheeses were found to give the best results when at the end of about three days' drainage they contained about 50 per cent water. Such cheeses were salted by sprinkling the entire surface lightly, replaced upon the drain boards for one day, salted again and piled in two's. After another day they received the third salting and were piled in three's for two days longer. A total of about 10 per cent by weight of salt was used to secure an absorption of 4 per cent. At the same time the water-content dropped to 40 to 43 per cent. After salting is completed, the cheeses are brushed and punched with holes to permit oxygen to enter.72 They are then ready for ripening.

170. Ripening of Roquefort.—The ripening of experimental Roquefort has required four to six months at a relative humidity of 85 to 90 per cent. This relative humidity is just below the equilibrium relative humidity of the cheese, hence permits a shrinkage of 2 to 4 per cent in the water-content of the cheese. This makes it possible to control the amount of surface slime developed.

If the relative humidity goes too high, the surface slime of bacteria and yeasts becomes very heavy, soft and almost liquid, and follows the openings into the cheese with resultant damage to appearance and flavor. Even under the conditions at Roquefort, this slime must be removed by rubbing or scraping several times to avoid injury to the cheeses, together with the production of bad odor and taste. If the humidity becomes too low, the surface becomes dry, hard and cracks open, the friable crumbly texture is injured, and there is considerable loss in weight. Salt forms about 4 per cent of the cheese. This is in solution in the water present, which is about 40 per cent, and makes a brine of about 10 per cent strength. This strength of brine does not prevent the growth of the Roquefort mold (Penicillium Roqueforti) but does hinder the development of Oidium lactis in the open spaces within the cheese. Accurate adjustment of temperature and relative humidity in the ripening rooms to salt and water-content in the cheese is essential to proper ripening. These conditions are furnished by the unique natural conditions of the caves of Roquefort. The production of such cheeses elsewhere depends either on the discovery of another locality with closely similar conditions or on the artificial production and control of the necessary temperature and relative humidity. This has been done on an experimental basis by the use of cold storage apparatus combined with proper humidifiers.

The differences between working with sheep's and with cow's milk lie in the making process rather than in the ripening. Sheep's milk freshly drawn shows a higher acidity than cow's milk, probably on account of the acid reaction of its greater casein content. With nearly double the total solids of cow's milk, the yield to one hundred pounds is much greater, consequently the drainage of the curd is much more easily handled.

Once made and salted, the cheeses require very nearly the same conditions of ripening. The resultant products are alike in appearance and texture. In flavor, cow's milk Roquefort differs in character from sheep's milk cheese to such a degree as to be recognized by taste. The difference was found by Currie73 to be due to an actual difference in the combination of fatty acids present.

Although these differences in character are recognizable by the expert in testing the cheese, as well as by chemical analysis, cow's milk Roquefort would satisfy that large proportion of consumers who use such cheese only in connection with other fairly high flavored foods. The demands for technical skill and factory equipment are not naturally greater than for many other lines of cheese-making. The gradual development of a cow's milk Roquefort may be anticipated.

171. Gorgonzola74 is a rennet cheese made from fresh whole cow's milk, in northern Italy. It takes its name from the village of Gorgonzola, a few miles from Milan, but the manufacture of the cheese has spread over a wide area. The cheeses are made on farms and in factories from which they are transported for ripening to cool valleys of the Alps, principally near Lecco (Fig. 24). Boeggild introduced the making of a cheese after the Gorgonzola process into Denmark about 1885. This industry has been successful on a small scale since that time. Gorgonzola cheeses are about 30 cm. (12 inches) in diameter and 18 cm. (7 inches) thick and weigh 15 to 20 pounds. As exported they are usually heavily coated75 with a mixture usually barite, tallow and lard colored with annatto or other cheese color. This coating prevents shrinkage or mold on the surface of the cheese in transit. When cut these cheeses vary greatly. All show marbling with mold (Roquefort mold). During their ripening they become very slimy at the surface. To open up air spaces for mold growth, this slime is scraped off and holes are punched into the cheeses. These holes are readily seen in the final product. Some show crumbly texture, well distributed mold, as in Roquefort, with flavor approaching that cheese; in others the texture is waxy rather than crumbly, a condition correlated regularly with different character in the flavor. Frequently in whole areas or in small pockets, slime consisting of bacteria and Oidium has followed the openings into the cheese and affects its odor and taste.

Experimental Gorgonzola cheeses comparable with the Italian product were made with cow's milk ripened as for Roquefort or higher, to 0.25-0.30 per cent (titrated as lactic acid), curdled at 86° F. (30° C.), cut into cubes and slightly stirred, then dipped to a draining board for about one-half hour, and put into the hoop. The cheeses drained quickly to about 50 percent water and developed a surface rind as in the harder cheeses. Cut surfaces showed a fairly open cheese in which mold grew readily. These cheeses were salted to taste, not to a specified percentage. They ripened with the same irregular results and the characteristic range of flavors found in Gorgonzola. To avoid the rotting of the cheese by surface growths, they were exposed to low humidities for a time and cracks opened at the surfaces, as seen in the ripening rooms at Lecco (Fig. 24). The texture was more or less waxy or tough, which was correlated with the slightly higher heat at renneting together with the stirring or "working" of the curd. Comparative analyses of a series of imported cheeses confirm the interpretation that the salt-content of Roquefort, 4 per cent approximately, prevents the invasion of the interior of the cheese by Oidium. No complete study of the ripening of Gorgonzola has been made. As far as followed, it consists in an initial souring process followed by ripening by molds and slime organisms. At its best, Gorgonzola is nearly equal to Roquefort but the percentage of such quality is low. In spite of its irregular quality, England has used larger amounts of Gorgonzola than of Roquefort. Considerable quantities have been imported for the Italian trade in the United States.

172. Stilton cheese bears the name of an English village76 in which it was first sold. It is made from cow's milk and is typically a whole milk cheese, although part skim cheeses are regularly made and sold as lower grades. In the Stilton-making counties, the milk from Shorthorn cattle testing about 3.5 to 4.0 per cent fat is preferred to richer or poorer grades. Such milk is curdled with rennet at about 86° F. in about one hour; the curd is cut, dipped to a draining table covered with cloth and drained slowly over a period of several hours, commonly overnight. During this period considerable acidity is developed. The curd is then milled or broken by hand, salted, packed into hoops 15 to 16 inches high and 7 inches in diameter. These hoops are made from heavy tin (Fig. 26) with four rows of holes about 3/10 inch in diameter. The freshly filled hoops are allowed to stand and drain without pressure in a room at about 70° F. (Fig. 26). Such cheeses are turned every day for several days. When solid enough to stand the hoops are removed, the cheeses are scraped or rubbed with a knife until the surface is smooth, and commonly wrapped with a cloth bandage to maintain the shape, if the cheese is still too soft to stand firmly. In the factories, several rooms are used with varying temperature and relative humidities, which makes it possible to place each cheese under the condition best suited to its texture and condition of ripeness. In general, the dairy sections of England are much more humid than those of America and there are less violent changes in temperature. Stilton cheese-making has grown up to take advantage of this climatic factor in handling the product. Transplantation of such an industry necessitates a mastery not only of the manipulations but a grasp of the fundamental principles underlying the process and a readjustment of practices to preserve those principles.

Stilton is, then, a soured curd cheese in whose ripening a very prominent part is played by the green mold (usually some strain of P. Roqueforti) which grows throughout the cavities of its mass77. At its best, it has attractive texture and flavor. Much of it fails to reach high quality on account of the invasion of bacteria, Oidium lactis, and very frequently myriads of cheese mites. The following analysis was furnished as typical for ripe cheese by Miles Benson,78 late professor of dairying at Reading, England: Water 31 per cent, fat 36 per cent, casein 29 per cent, mineral constituents including salt about 4 per cent. Approximately the same figures are given by Primrose McConnell (Agricultural Note Book). The low percentage of salt is another factor of uncertainty in the control of this Stilton product, as in Gorgonzola, since these cheeses are commonly high in water-content at first and are thus subject to invasion by Oidium.

Stilton has been made on a small scale in Canada79 and occasionally attempted in the United States. No serious effort to develop an industry of commercial importance has been made in America. Comparative study of the cheeses ripened by green mold tends to the conviction that the adaptation of the Roquefort practice to the use of cow's milk offers a more satisfactory basis for experiment than efforts to establish a Stilton or a Gorgonzola industry.

173. Gex.—A cheese under this name made in southern France resembles, in its general character as a ripened cheese, the English Stilton and Italian Gorgonzola. Although it has no commercial importance, reference is made to this cheese to show that mold-ripened cheeses have been developed entirely independently in different countries to bring about the same general character of product.

174. Bacterially ripened series.—The semi-hard cheeses ripened by bacteria stand half-way between true Limburger and the hard forms. In fact, brands of Limburger are readily found which approach the texture and ripening of Brick cheese. In the same way, Brick cheeses are often found which have the appearance, texture and much of the flavor of the Cheddars with only a trace of the taste of Limburger. Port du Salut, Oka, Münster, in France Livarot, in the Balkan regions Kascoval, belong in this series.

175. Brick cheese.—The name of this cheese is probably due to the finished product being about the size and shape of a brick. It is similar to the German cheese Bäckstein and may have been developed from it. It is typically a sweet-curd cheese, made from milk freshly drawn, without permitting the development of appreciable quantities of acidity until after the curd has been put into the hoop. In the making process, it is intermediate between Limburger and the cheeses of the Cheddar group. Some cheese-makers use an ordinary cheese vat, others a copper kettle in manufacturing.

The discussion of the care of milk in Chapter II applies to that for Brick cheese. For the best quality of cheese, the milk in the vat should show about 0.15 of 1 per cent acidity and never above 0.18 of 1 per cent.80

176. Making of Brick cheese.81—The milk is received at the cheese factory at a temperature of about 92° to 96° F. For the best results, the acidity should be determined (by the acid test) to decide on the amount of starter to use. Few Brick cheese-makers use an acid test or a starter but these precautions would improve the product of many factories. For method of using the acid test, see Chapter V. Chapter IV discusses the preparation and use of starter. Usually 0.25 to 0.50 of 1 per cent of starter is the amount required. A small amount of starter is used to aid the development of lactic acid and for the beneficial effect it has on the flavor. A very small development of acid is desired after adding the starter; therefore the change in acidity should be very carefully watched with the acid test. The vat is usually set when the acid test shows 0.16 of 1 per cent acidity. The more acid in the milk, the less starter should be employed. Sufficient rennet extract should be used to give a coagulation suitable for cutting in thirty to thirty-five minutes. For method of adding the rennet extract, see Chapter V. When the coagulum is firm enough for the curd to break clean over the finger, it is ready to cut. The curd is cut with coarse knives into ⅜- or ½-inch cubes. After cutting, the curd is let stand three to five minutes, then stirred with the hands for a few minutes until the whey begins to separate and then stirred with the rake. Some makers do not stir by hand but use the rake directly after cutting. When this is done, great care must be exercised to stir the curd without breaking up the pieces, because this causes a loss of fat. After cutting the curd is stirred for twenty to thirty minutes before the steam is turned on. The curd is heated very slowly at first and more rapidly during the last stages of cooking. The curd is cooked to a temperature of 110° to 115° F. The lower the temperature that can be used to produce firm curd, the better the texture of the cheese. After cutting and during the cooking, the curd must be constantly stirred so that lumps will not form. When the curd forms lumps, the moisture is not evenly expelled. This results in uneven texture and curing. Sometimes some salt is added to the curd in the vat to restrain souring. The curd is stirred after cooking until it is sufficiently firm. It remains usually in the whey for a total period of one and one-fourth to one and one-half hours from the time of cutting. It is then dipped into forms 10 inches long by 5 inches wide by 8 inches deep. The forms are without top or bottom and are placed on a draining table. This table is so constructed that the whey can be saved for stock feed. When ready to "dip," the whey is drawn down to the surface of the curd in the vat, then the curd is dipped into the forms or hoops. Care must be taken to get the same amount of curd into each form to produce the cheeses of uniform size. Each cheese is turned several times to insure even draining and even reduction of the temperature. While draining, a follower is placed in each hoop and a weight placed on each cheese. Usually a brick is used for this weight. A cheese is allowed to drain or press for ten to fifteen hours. It is then placed on the salting table and rubbed with coarse salt. While on the salting table, a cheese is placed on its broad side. Some cheese-makers prefer to salt their cheeses by soaking them in a salt brine. This brine should be strong enough to float an egg. Salting requires three days. The cheeses are then brushed free from excess salt and taken to the cellar to cure or ripen.

177. Ripening Brick cheese.—For this process, the cellars are kept at about 90 percent relative humidity and a temperature of 60° to 65° F. Some prefer a temperature for curing as high as 68° F. During the curing, the surfaces of the cheese are kept moist and mold growths kept down by rubbing or brushing the cheese with pure water or salt and water. In the curing cellars the cheeses are placed on shelves; at first they are set close together and as they cure, they are separated. During curing, the color changes from a whitish to a reddish brown. The cheese cures from the outside toward the center. When first made, the product is harsh and hard in texture but during the ripening process it becomes mellow and smooth. The cheeses remain on the curing shelves for four to six weeks, after which they are wrapped in heavy waxed paper and boxed. A cheese ready for market usually weighs about five pounds. A Brick cheese box is 5 inches deep by 20 inches wide by 3 feet long, and holds 110 to 115 pounds of cheese.

178. Qualities of Brick cheese.—The cheeses should be neat and attractive and the rind not cracked or broken. The sides should be square and not bulged. The cheese should have a clean, characteristic Brick cheese flavor. The body and texture should be mellow and smooth and when rubbed between the thumb and forefinger, should break down like cold butter. The color should be uniform. The cheese should contain the proper amount of salt and moisture. One of the worst faults with Brick cheese is bad flavor. This is many times due to the cheese-maker not using clean flavored starter. It may also be due to bad flavored milk. A Brick cheese-maker has no means of controlling gassy fermentations. These show themselves in the bad flavor of the cheese and in the porous body. They also cause the cheese to bulge. If detected, gassy milk should be rejected. If too much acid is developed, a sour cheese is the result. This will not cure normally and usually has a sour flavor. The body will be brittle and mealy. If too much salt is used, the cheese may have a salty taste and it will cure very slowly. If not enough salt is used, the cheese may cure too rapidly and undesirable flavors and fermentations develop. The cheese must have the proper moisture-content; if too much moisture is present, the cheese cures too fast and is soft and pasty in body; if not enough moisture, then the reverse is true. Tabulation of cheeses of special quality, as submitted in scoring contests, show an average water-content of 37 to 38 per cent, with occasional cheeses verging toward Limburger in texture and flavor with 40 to 42 per cent water, and others indistinguishable from Cheddar, with water-content as low as 34 per cent.

The Wisconsin Cheese-makers Association uses the following score-card for the judging of Brick cheese on a scale of 100:

179. Composition and yield.—The composition of Brick cheese varies within wide limits. The average cheese probably contains from 37 to 39 per cent of water, although many cheeses are above and below this average; Doane and Lawson82 give the fat as 28.86 per cent, proteins 23.8 per cent and total ash 4.20 per cent.

The composition and yield are both affected by: (1) the moisture-content of the cheese; (2) composition of the milk from which made; and (3) losses during the manufacturing process. The average yield of Brick cheese is 11 to 13 pounds to 100 pounds of milk.

180. Port du Salut cheese.—The Trappist monks originated this type of cheese in their monasteries in France. Under the name of their community Oka, it has been made and sold widely by the Trappist Fathers of Quebec. In recent years, factories independent of the order have made such cheese both in America and in Europe.

The following outline of the making process indicates the close relationship between Port du Salut and Brick cheeses. Whole milk or milk not over one-fifth skimmed is ripened to medium acidity, then heated to 90° to 95° F. according to season and acidity. Rennet enough is added (see Chapter V) to curdle in thirty to forty minutes, although some makers shorten the time to twenty minutes. When formed, the curd is cut into small cubes and excess of whey is dipped away. The constantly stirred mass is then heated or cooked to 100° to 105° F. within a period of ten to twelve minutes or according to some makers twenty to thirty minutes. It is allowed to stand a few minutes to settle. Most of the whey is then drawn and the mass is stirred vigorously to prevent fusion of the curd granules. The curd is ready for the hoop when the particles are about the size of grains of wheat and do not stick together when squeezed with the hand. The individual grains of curd should crumble easily between the fingers. The hot curd is transferred directly to the hoops without cooling. For this purpose, a hoop is set upon the table covered with a cloth and the curd dipped into the cloth. The edges of the cloth are then folded over. In this condition the cheese is transferred to the press where gradually increasing pressure begins with 3 to 4 pounds and reaches about 70 pounds. To insure proper shape, cheeses are turned and put into fresh cloths at the end of the first hour and turned subsequently several times during the pressing period of about twelve hours.83

Port du Salut cheeses are salted by rubbing fine salt on the surface by hand at the rate of 1.2 to 2 per cent of the weight of the cheese. After about two days in the salting process, they are put into the ripening cellars. The cellars are wet, since they reach 90 to 95 per cent relative humidity at a temperature of about 55° F. After two days in the cellar, the cheeses are plungedto the shelves where they are rubbed every day into a tank of saturated brine to which a trace of cheese color has been added. As they come out of these tanks, they are yellowish and greasy or slimy. They are returned with a cloth or by hands wet in brine. After about one week they are again plunged in the brine. Treatment with brine tends to insure a firm rind. The cheeses are rubbed more or less regularly with brine through the whole ripening period.

After six weeks, such cheese may be eaten. The cut surface of Port du Salut is creamy in color, may or may not show small holes. In texture it is soft enough to spread readily under pressure without losing its shape in handling. In flavor the cheese is a mild form belonging to the Limburger group.

Port du Salut cheeses as imported from France usually are firm round cakes about 1½ inches thick, weighing about 3 pounds.

CHAPTER XI

THE HARD CHEESES

The hard cheeses form a great series of groups, whose most prominent physical character is their firm or hard texture. This is correlated with comparatively low water-content, which is usually between 30 and 40 per cent. Although certain varieties occasionally test above 40 per cent water, this deviation is accompanied by quick ripening and rapid spoilage. These varieties of cheese are staple products with long marketable periods; therefore they may be handled in large lots, shipped, carted and stored freely without the losses such treatment would entail in soft cheese. The retailer frequently buys hard cheese by the ton, not by the cheese or by the box.

In making, these varieties are characterized as cooked and pressed cheeses. Although both the heating of a curd and the pressing of a newly made cheese occur among semi-hard forms, these practices appear in their most typical forms in the hard cheeses.

The hard cheeses show two types of texture. A cut cheese may appear smooth, free from holes or with a few angular cracks or seams, or it may show round holes or "eyes." In the smooth textured forms every effort is made to prevent gassy fermentations, usually by controlling the fermentation of the curd in the making process. When "eyes" are present, the end sought has been a development of a particular form of gassy fermentation which gives this appearance and brings about the characteristic ripening texture and flavor.

The hard cheeses have been developed in groups of national varieties. The best known of these groups are those which may be represented by English Cheddar, American Factory Cheddar, Danish, the Edam of Holland, Swiss and Parmesan with many related varieties in Italy and neighboring countries of southern Europe.

181. The Danish group.—The Danish cheeses are related in appearance and flavor to the English group represented by Cheddar. The demand for butter in Europe has been so great that the Danish cheese-makers have developed skim and part skim varieties largely to the exclusion of the whole milk form. Skillful handling of their process has resulted in a product which has had a very large and appreciative market in England and Germany.

182. The Dutch group.—Edam and Gouda are the two forms of cheese made in Holland and most widely known among other peoples. Both reach America in considerable quantities; both are shipped in large amounts to tropical countries. Although attempts have been made to manufacture them in America, no commercial production of these cheeses has been successful. Although whole milk grades of these cheeses are known, they are to a large measure part skim in manufacture. The presence of one or both of these forms in every large market in America makes the general facts of their production of general interest. Parts of a report on experimental work in the making of Edam and Gouda are, therefore, given here.

183. Edam cheese84 is a sweet-curd type, made from partially skimmed-milk. It comes to the market in the form of round red balls, each weighing from 3½ to 4 pounds when cured. It is largely manufactured in northern Holland and derives its name from a town famous as a market for this kind of cheese.85 Milk from which one-fourth to one-third of the fat has been removed is used. Too great pains cannot be taken in regard to the condition of the milk. It should be fresh, free from every trace of taint; in brief, it should be in as perfect condition as possible.

184. Method of manufacture.—The following paragraphs give the steps in the manufacture of Edam cheese:

Addition of rennet to milk.—The rennet should not be added until the milk has reached the desired temperature (85° to 88° F.) and this temperature has become constant. When the temperature reaches the desired point and remains there stationary, the rennet extract is added. Rennet extract may be used, 4½ to 5½ ounces being taken for 1000 pounds of milk, or enough to coagulate the milk in the desired time, at the actual temperature used. The milk should be completely coagulated, ready for cutting, in about twelve to eighteen minutes from the time the rennet is added. The same precaution observed in making Cheddar cheese should be followed in making Edam cheese with reference to care in adding the rennet, such as careful, accurate measurement, dilution with pure water before addition to milk.

Cutting the curd for Edam.—When the curd breaks clean across the finger, it should be cut; it is cut a very little softer than in the Cheddar process as ordinarily practiced. As stated, this stage of hardness in the curd which fits it for cutting should come in twelve to eighteen minutes after the rennet is added. First, a vertical knife is used and the curd is cut lengthwise, after which it is allowed to stand until the slices of curd begin to show the separation of whey. Then the vertical knife is used in cutting crosswise, after which the horizontal knife is at once used. Any curd adhering to the bottom and sides of the vat is carefully removed by the hand, after which the curd-knife is again passed through the mass of curd lengthwise and crosswise, continuing the cutting until the curd has been cut as uniformly as possible into very small pieces.

Treatment of Edam curd after cutting.—When the cutting is completed, one commences at once to heat the curd up to the temperature of 93° to 96° F. The heating is done as quickly as possible. While the heating is in progress, the curd is kept constantly agitated to prevent settling and consequent overheating. As soon as the curd shows signs of hardening, which the experience of the worker will enable him to determine, the whey is drawn off until the upper surface of the curd appears, when one should commence to fill the press molds.

Filling molds, pressing and dressing Edam.—The molds, which are described later in detail, are well soaked in warm water previous to use, in order to prevent too sudden chilling of curd and consequent checking of separation of whey. As soon as whey is drawn off, as indicated above, one begins to fill the pressing molds (Fig. 27). The filling should be done as rapidly as possible to prevent too great cooling of curd. When the curd has been put Fig. 27.—Edam cheese mold. into the molds, its temperature should not be below 88° F. Unless care is taken to keep the curd covered, the portion that is last put into the molds may become too much cooled. In making Edam cheese on a small scale, it is a good plan to squeeze the moisture out with the hands as much as possible and then break it up again before putting in the molds, when the curd should be pressed into the mold firmly by the hands. The molds should be filled as nearly alike as possible. The cheese should weigh from 5 to 5¼ pounds each when ready for the press. When the filling of molds is completed, they are put under continual pressure of 20 to 25 pounds for about twenty-five or thirty minutes. While the cheese is being pressed, some sweet whey is heated to a temperature of 125° or 130° F., and this whey should not be allowed to go below 120° F. at any time while it is being used. When the cheeses are taken from their molds, each is put into the warm whey for two minutes, then removed and dressed. For dressing Edam cheese, the ordinary cheese bandage cloth is used. This is cut into strips, which should be long enough to reach entirely around the cheese and overlap an inch or so, and which should be wide enough to cover allbut a small portion of the ends of the cheese when put in place. Before putting on the bandage, all rough projections should be carefully pared from the cheese. In putting on, the cheese is held in one hand and the bandage is wrapped carefully around the cheese, so that the whole is covered, except a small portion on the upper and lower surface of the cheese. These bare spots are covered by small pieces of bandage cloth of a size sufficient to fill the bare surface. The bandage is kept wet with the warm sweet whey, thus facilitating the process of dressing. After each cheese is dressed, it should be replaced in the dressing mold, care being taken that the bandage remains in place and leaves no portion of the surface of the cheese uncovered and in direct contact with the mold. The cheese is then put under continual pressure of 60 to 120 pounds and kept for six to twelve hours.

185. Salting and curing Edam.—There are two methods which may be employed in salting,—dry and wet. In dry-salting, when the cheese is finally taken from the press, it is removed from the press mold, its bandage is removed completely, and the cheese placed in another mold, quite similar, known as the salting mold. Each cheese is placed in a salting mold with a coating of fine salt completely surrounding it. The cheese is salted in this way once each day for five or six days. Each day the cheese should be turned when it is replaced in the mold, so that it will not be rounded on one end more than the other.

In the method of wet-salting, the cheese is placed in a tank of salt brine, made by dissolving common salt in water in the proportion of about 1 pound of salt to 2½ quarts of water. Each cheese is turned once a day and should be left in the brine seven or eight days. When the cheese is taken from the salting mold or salt bath, it is placed in warm water and given a vigorous, thorough brushing in order to remove all slimy or greasy substances that may have accumulated on the outer surface. When the surface is well cleansed, the cheese is carefully wiped dry with a linen towel and placed upon a shelf in the curing-room. In being put on the shelves, the cheeses should be placed in contact so as to support one another, until they have flattened out at both ends so much that they can stand upright alone. Then they are moved far enough apart to allow a little air space between them. Another method of securing the flattened ends is to support each cheese on opposite sides by wedge-shaped pieces of wood. After being placed on the shelves in the curing-room, they are turned once a day and rubbed with the bare hand during the first month, twice a week during the second month and once a week after that. When any slimy substance appears on the surface of the cheese, it should be washed off at once with warm water or sweet whey. The special conditions of the curing-room will be noticed in detail below. When the cheeses are about two months old, they can be prepared for market in the following manner: They are first made smooth on the surface by being turned in a lathe or in some other manner, after which the surface is colored. For coloring, some carmine is dissolved in alcohol or ammonia to secure the proper shade, and in this color-bath the cheeses are placed for about one minute, when they are removed and allowed to drain, and as soon as they are dry the outside of each cheese is rubbed with boiled linseed oil, in order to prevent checking. They are then wrapped in tin-foil, which is done very much like the bandaging. Care must be taken to put on the tin-foil so that it presents a smooth, neat appearance. The cheeses are finally packed in boxes, containing twelve cheeses in each box, arranged in two layers of six each with a separate partition for each cheese.

186. Equipment for making Edam cheese.—Careful attention must be given to the moisture and temperature of the curing-room. This room should be well ventilated, quite moist and its temperature kept between 50° and 65° F. These are conditions not easy to secure in any ordinary room. Some form of cellar is best adapted for these conditions. The amount of moisture can be determined by an instrument known as a hygrometer. In a curing-room suited for Edam cheese, the moisture should be between 85 and 95 per cent, or a little short of saturation. When the temperature is between 50° and 65° F., the moisture is between 85 and 95 per cent if the wet-bulb thermometer is from 1 to 2° F. (or ½ to 1° C.) below the dry-bulb thermometer. Cheese will check or crack and be spoiled for market, if the degree of moisture is not kept high enough.

Aside from the molds, press and salting vat, the same apparatus that is used in making Cheddar can be used for Edam cheese. The pressing mold is turned preferably from white wood or, in any case, from wood that will not taint. Each mold consists of two parts; the lower constitutes the main part of the mold, the upper portion is simply a cover. The lower portion or body of the mold has several holes in the bottom, from which the whey flows when the cheese is pressed. Care must be taken to prevent these holes being stopped up by curd. This part of the mold is about six inches deep and six inches in diameter across the top. The salting mold has no cover and the bottom is provided with only one hole for the out-flow of whey; in other respects it is much like the pressing mold.

187. Qualities and yield of Edam cheese.—The flavor of a perfect Edam cheese is difficult to describe. It is mild, clean, and pleasantly saline. In imperfect Edams, the flavor is more or less sour and offensive. In body, a perfect Edam cheese is solid, rather dry and mealy or crumbly. In texture, it should be close and free from pores. In the experiments here reported the amount of fat in 100 pounds of the partially skimmed-milk varied from 2.45 to 3.20 pounds and averaged 2.77 pounds. Of this amount, from 0.30 to 0.51 pound of fat was lost in the whey, with an average of 0.39 pound. The yield of cheese from 100 pounds of milk varied from 9.60 to 11.82 pounds and averaged 10.56 pounds.

188. Gouda cheese.86—This Dutch variety is a sweet-curd cheese made from whole milk. In shape, the Gouda cheese is somewhat like a Cheddar with the sharp edges rounded off and sloping toward the outer circumference at the middle from the end faces. They usually weigh 10 or 12 pounds, though they vary in weight from 8 to 16 pounds. They are largely manufactured in southern Holland, and derive their name from the town in which they were first made. Fresh sweet milk that has been produced and cared for in the best possible manner should be used.

189. Method of manufacture.—The processes of manufacturing Gouda cheese are as follows:

Treatment of curd after cutting.—After the cutting is completed, heating and stirring is begun at once. The heating and constant stirring is continued until the curd reaches a temperature of 104° F., which should require from thirty to forty minutes. When the curd becomes rubber-like in feeling, the whey should be run off. The whey should be entirely sweet when it is removed.

Pressing and dressing Gouda.—After the whey is off, the curd is put in molds at once without salting (Fig. 28). Pains should be taken in this process to keep the temperature of the curd as near 100° F. as possible. Each cheese is placed under continuous pressure amounting to ten or twenty times its own weight and kept for about half an hour. The first bandage is put on in very much the same manner as in Edam cheese making. The cheese is then put in press again for about one hour. Fig. 28.—Gouda cheese mold. The first bandage is then taken off and a second one like the first put on with great care, taking pains to make the bandage smooth, capping the ends as before. The cheese is then put in press again and left twelve hours or more.