W. W. Fisk

A bacterially-ripened series of cheeses parallels the mold-ripened group as typified by Camembert. Although the varieties overlap, these may be roughly grouped as: (1) those made from friable or soft curd; (2) those made from firm or rubbery curd. In the first group, the curd is set at 86° F., or below; in the second, the rennet is added at 90° F. or above. In the first, the lower temperature and long curdling time with ripened milk gives a soft friable curd which may be toughened somewhat by cutting and stirring in the whey. This section is typified by d'Isigny, American Brie, Liederkranz. In the second, curdling of unripened milk at temperatures of 90° F. or above insures a smooth elastic curd which fuses more or less completely into the firm rubbery mass typified by freshly made Limburger.

155. The Isigny group.—A series of names, d'Isigny, Brie, Brie d'Isigny, combined with trade names, are used for a domestic cheese, made in a small number of factories distributed over New York, Pennsylvania, Michigan, Illinois, Wisconsin, Iowa and California. The cheeses sold under the separate varietal names differ only in diameter; their thickness is fairly uniform; the process of manufacture and ripening with resultant textures and flavors furnishes no fundamental varietal characters, although the products of the several factories show noticeable differences in market quality. D'Isigny, while the name of a French town famous for butter production, is not used to designate a cheese in France. It may, therefore, be accepted as a French name arbitrarily applied to a domestic product. Brie as used in France is a markedly different cheese (p. 131), and the name should be dropped from this form as made in America. As used for a member of this series made in America, it merely means cheese 7 to 15 inches in diameter. The cheese partakes of the characters of French Livarot, and of Pont l'Eveque without exactly reproducing either form.

The milk varies from separator skim to whole milk, with resultant differences in quality. Freedom from gas is essential to the best results. The milk is curdled at 85° to 86° F. with sufficient rennet to produce a very firm curd within a period of one and one-half hours. Curd is then cut in two directions, allowed to stand a few minutes or gently agitated to produce a very slight toughness or "worked" condition, then scooped into hoops 4½ to 5 inches in height and varying in diameter from 2½ to 15 inches according to the size selected for manufacture. To aid in the escape of whey, three rows of holes ?12 inch in diameter and 2 inches apart in the row are made in each hoop. The hoops are arranged upon draining tables with more or less corrugated surface, which for best drainage should be covered with matting. The cheeses are allowed to drain without pressure. They are commonly turned the second morning, although they are sometimes solid enough to turn within the first day. When fully drained, the cheeses are salted by rubbing coarse salt on the surface, after which they stand an extra day. They are then arranged upon shelves in a ripening room held between 50° and 60° F. with humidity so high that evaporation is kept at a minimum. In this room, a surface slime develops quickly. This consists of bacteria of several forms, yeasts, Oidium lactis and accidental species of other molds. During this ripening, the cheeses are turned, rubbed with the hands, washed with salt water and scraped if infected with molds which produce colored colonies. In the course of ripening, the slimy surface layer acquires a yellowish orange color with the strong odor and taste characteristic of the series.

Brands of d'Isigny are made from every grade between separator skim and whole milk. They reach the market in condition all the way from "Kosher" forms56 which are eaten entirely unripe, to brands which approximate the qualities of Limburger and others which approach Port du Salut.

The biology and chemistry of the ripening of this type of cheese have not been completely followed. An initial souring process always takes place quickly. Oidium lactis is always present in some degree on the surface, but the organisms in the yellowish to orange slime on the surface of the cheese appear to produce the characteristic odor and taste. These appear to be due to the development of volatile fatty acids, such as valerianic and caproic, which diffuse throughout the cheese, even penetrating the unripened sour portions. The same odor and taste in varying intensity are present in Limburger, Brick, and a long series of German varieties not handled in America.

High-flavored cheeses such as these, form an acceptable part of the meal in cases in which the intensity of other flavors is such as to mask entirely the milder flavors of Camembert or cream cheese.

In composition, a characteristic whole-milk brand of this group showed the following analysis:57 water, 45.5 per cent; fat, 25.28 per cent; protein, 18.22 per cent.

156. RaffinÉ.58—This cheese is made in the French settlement of the Isle of Orleans in the St. Lawrence River. The practice seems to have been brought from France and represents an intermediate product between Camembert and perhaps Livarot, a cheese on the borderline between Camembert and Isigny as made in America. The outline of the making process as given follows: Milk freshly drawn is curdled without cooling, at approximately 90° F. The rennet is prepared on the farm. About one-half hour is required for curdling. The curd is cut into 2-inch cubes. Whey is removed as fast as it separates. About two hours are required for draining. The curd then goes into the hoops. The metal hoops, which are closed at one end, are 6 inches high, 4½ inches in diameter, with holes about ?16 inch at intervals of about ½ inch, and stand upon three legs about 1 inch in height. When filled, the cheeses are left on a draining table. Some salt is put on top while draining. When the volume is reduced to one-half, the cheese is turned. The draining room is kept at about 70° F. After they are firm enough to handle, drainage is completed on racks covered with rush matting. These are arranged on special racks. The cheeses are turned twice a day, and washed in slightly salted water every two days. After each washing, they are drained for two hours on cloth, and placed on clean matting. This treatment continues about fifteen days.

After fifteen days on the matting, the cheeses are ready for ripening. They are first covered with cold brine and let stand twenty-four hours. The cheeses are packed in rolls or tiers in boxes, covered with cloth and ripened at 45° F. They must be kept moist; if signs of drying appear, moisture must be added. If the cheeses develop yellow slime, they are washed with clear water and rinsed in water with salt added. After a ripening period of three weeks, the cheeses should begin to be soft when pressed with the finger. The growth of molds must be prevented by washing the boxes, cloths, and washing and scraping the cheeses if necessary. When the cheeses are ready for the market, they are scraped clean and white, wrapped separately in cheese-cloth or parchment paper and packed into the boxes. Ripe cheeses are about 5 inches in diameter, 1 inch thick and weigh a little over 5 ounces.

The outline of the RaffinÉ process follows:

coagulation by rennet	30 minutes
cutting and draining curd	2 hours
draining in hoops	10 hours
stand on mats	15 days
ripening in boxes	21 days
Total period	36 days

The treatment described closely resembles the handling of Livarot cheese in the department of Calvados, France.

157. Liederkranz cheese.—Among the specialties in the bacterial group is Liederkranz, made from curd with the soft friable texture of a Camembert, molded in rectangular blocks of about 4 ounces in weight and ripened very completely. Although this name is the private brand of a single factory, it has become widely known with the effect of creating a type name in the American market. Analysis of this brand of cheese gives about 55 per cent water, 25 per cent fat, 17 per cent protein, which indicates a whole milk cheese.

158. Limburger cheese59 derives its name from the town of Limburg in Belgium. The manufacture of this cheese is now widely practiced in Europe and in certain parts of the United States, especially in New York and Wisconsin. Practically no cheese of this name is at present imported, and the practices described are limited to those in American factories.

159. The milk.—Limburger cheese is probably best known on account of its pronounced odor. Because of this characteristic pungent smell, it is often thought that the cheese is made in dirty or unsanitary places. On the contrary, Limburger cheese is usually made in small factories which are clean and sanitary. Because of the constant attention required, a cheese-maker can handle only about 2000-2500 pounds of milk a day, and then some help is necessary to care for the cheeses in the curing room.60 The discussion of the milk given in Chapter II applies to that to be made into Limburger cheese; however, Limburger requires sweeter milk than do some of the other types. To be sure of obtaining very sweet milk, it is the usual practice for the milk to be delivered without cooling morning and evening at the cheese factory. The cheese is made twice a day. Because the milk must be delivered twice daily, it is obtained from only a few producers near the factory. A factory usually does not have more than eight to twelve patrons. Because of the small number of patrons, it is comparatively easy to obtain a supply of fresh clean milk.

Fig. 23.—A common type of Limburger cheese factory.

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.

Limburger cheese should be regular in shape. The rind should not be cracked or broken nor the sides bulged, nor should it be lopsided. It should have the pronounced characteristic flavor, without other objectionable flavors due to undesirable fermentations. The body should be uniform throughout. It is common to find cheeses that have not a uniform body, due to lack of curing; a small part of the interior at the center will be hard and not cured, while the remainder of the cheese will be soft and buttery. The color should be uniform. When not entirely cured, the uncured part at the center is usually of a lighter color.

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.