The Book of Cheese

by Charles Thom; W. W. Fisk

DEFECTS IN CHEDDAR CHEESE

A great number of defects may occur in Cheddar cheese. Certain of these are due to known causes and proper remedies are definable, while neither cause nor remedy has been found for other defects. Some of the common defects and their causes and remedies are discussed under different headings of the score-card as: defects in flavor, their causes and remedies; defects in body and texture, their causes and remedies; defects in color, their causes and remedies; defects in finish and their causes and remedies.

251. Defects in flavor.—Any flavor differing from the characteristic Cheddar cheese is a defect. Certain of these defective flavors can be recognized and causes and remedies given for them, while others may be distinguished as such but no cause or remedy can be given.

252. Feedy flavors.—Flavors may be characteristic of certain feeding stuffs. Feeding strong-flavored foods, such as turnips, cabbage, decayed silage, certain weeds and sometimes rank green feed, give their peculiar flavors to both milk and cheese. Freshly drawn milk usually absorbs these odors from the air in barns filled with such foods. Certain of these materials may be fed just after milking in moderate amounts without affecting the milk drawn at the next milking. Others should not be used. Milk should not be exposed to strong volatile odors. Some of the objectionable odors may be removed by airing the curd for a longer time after milling before the salt is applied.

253. Acid flavors.—A cheese with an acid flavor has a pronounced sour smell and taste. This is caused by the over-development of acid which may be due to any of the following causes: (a) receiving milk at the factory which is sour or has too high development of acid; (b) using too much starter; (c) ripening the milk too much before adding rennet; (d) not firming the curd sufficiently in the whey before removing the latter; (e) developing too much acid in the whey before it is removed; (f) retaining too much moisture in the curd.

The trouble can be reduced or eliminated by one or more of the following precautions: (a) receiving only clean, sweet milk at the cheese factory; (b) maintaining the proper relation between the moisture and acidity; (c) adding the rennet at the proper acidity; (d) using less starter; (e) adding the rennet extract so that there will be sufficient time to firm the curd before the acid has developed to such a stage that it will be necessary to draw the whey; (f) producing the proper final water-content in the newly made cheese.

254. Sweet or fruity flavors.—These are the sweet flavors characteristic of strawberry, raspberry and the like. Such flavors are very objectionable and usually increase with the age of the cheese. They appear to be caused by: (a) carrying both milk and whey in the same cans without properly cleaning them; (b) exposing milk near hog-pens where whey is fed; (c) dirty whey tanks at the cheese factory; (d) micro-organisms which get into the milk through any unclean conditions.

These troubles can be controlled: (a) if milk and whey must be carried in the same cans, the cans should be emptied immediately on arrival at the farm and thoroughly washed and scalded; (b) the whey vat at the factory should be kept clean and sweet; (c) the starter must have the proper clean flavor.

Other defects may be classed as "off flavors," "dirty flavors," "bitter flavors" and the like. These are undoubtedly due to unsanitary conditions whereby undesirable organisms get into the milk, even though the particular organism is often not determined. The flavors may be improved by the use of a clean-flavored commercial starter and by airing the curd after milling before salting. The best remedy is to remove the source of the difficulty.

255. Defects in body and texture.—The body and texture should be close. A sample rubbed between the thumb and fingers should be smooth and waxy. Any condition which causes a body and texture other than this is to be avoided.

256. Loose or open texture.—A cheese with this defect is full of irregularly shaped holes and usually soft or weak-bodied. This is serious if the cheese is to be held for some time. Moisture and fat are likely to collect in these holes and cause the cheese to deteriorate, thereby shortening its commercial life.

Several causes may bring about this condition: (a) insufficient cheddaring; (b) pressing at too high a temperature; (c) inadequate pressing; (d) development of too little acid.

The corresponding remedies are: (a) cheddar the curd until the holes are closed and the curd is solid; (b) cool the curd to 80° F. before putting to press; (c) press the curd longer, possibly twenty-four to twenty-six hours; (d) develop a little higher acid in the whey before removing the curd.

257. Dry body.—A cheese with this defect is usually firm, hard and dry, sometimes rubbery or corky. This may result from lack of moisture, fat or both, and may be due to the following causes: (a) making the cheese from partly skimmed-milk; (b) heating the curd in the whey for too long a time; (c) heating the curd too high; (d) stirring the curd too much in the whey or as the last of the whey is removed; (e) using too much salt; (f) developing of too much acid in the whey; (g) curing the cheese in too hot or too dry a curing-room; (h) not piling the curd high or fast enough in the cheddaring process.

The cause should be located and the corresponding remedy found, as follows: (a) make cheese only from whole milk; (b) draw the whey sooner; (c) firm the curd at as low temperature as possible in the whey; (d) stir the curd in the whey only enough to keep the curd particles separated but do not hand-stir it; (e) use less salt; (f) develop less acid in the whey; (g) cure the cheese in a cool moist curing-room; (h) pile the curd sooner and higher during the cheddaring process.

The number of causes which may singly or in combination produce dry cheese demands experience and technical skill that calls for the development of a high degree of judgment.

258. Gassy textured cheese.—Gassy cheese has large numbers of very small round or slightly flattened holes. When round these are called "pin-holes," and when slightly flattened "fish eye" openings. These are due to the formation of gas by the micro-organisms in the cheese. When a cheese is gassy, it usually puffs up from gas pressure as in the rising of bread. If enough gas is formed, it will cause the cheese to break or crack open. Instead of being flat on the ends, such a cheese becomes so nearly spherical as to roll from the shelf at times.

The gas-producing organisms enter because of unclean conditions somewhere in the handling of the milk and the making of the cheese. Some of the common sources of gas organisms are: (a) unclean milkers; (b) dirty cows; (c) aërating the milk in impure air, especially air from hog-pens where the whey is fed; (d) allowing the cows to wade in stagnant water or in mud or in filthy barnyards and then not thoroughly cleaning the cows before milking; (e) exposing the milk to the dust from hay and feed; (f) dirty whey tanks; (g) drawing milk and whey in the same cans without afterward thoroughly washing them; (h) unclean utensils in the factory; (i) using gassy starter; (j) ripening cheese at high temperatures.

Some of these causes are within the control of the cheese-maker after the making process is begun. Many of them are avoided only by eternal vigilance. Among the recommendations for meeting gassy curd are the following: use only milk produced under clean sanitary conditions; use a clean commercial starter.

If gas is suspected in the milk, a larger percentage of commercial starter should be used. More acid must be developed before the whey is removed. If the gas shows while cheddaring, the curd should be piled and repiled until the holes flatten out before milling.

The curd should be kept warm during the piling or cheddaring process. This may be accomplished by covering the vat and setting a pail or two of hot water in it. After milling, the curd should be stirred and aired for a considerable length of time before salting. This will aërate the curd and allow it to cool. The cheese should then be placed in a cool curing-room. (See handling of gassy milk.)

259. Acidy, pasty or soft body and texture.—A cheese with acidy body may be either hard and dry or soft and moist. It has a mealy or sandy feeling when rubbed between the fingers. The causes and remedies are the same as for cheeses with acid flavors. When rubbed between the fingers, it is pasty and sticks to the fingers. It is caused by the cheese containing too much water. (See control of moisture.)

260. Defects in color.—Any color which is not uniform is a defect. The proper color depends on the market requirement. Some markets prefer a white and others a yellow cheese; however, if the color is uniform, it is not defective.

Mottled color is a spotted or variegated marking of the cheese. Several causes may give the same general effect: (a) uneven distribution of moisture, the curd having extra moisture being lighter in color; (b) neglecting to strain the starter; (c) adding the starter after the cheese color has been added; (d) mixing the curd from different vats.

Remedies for this mottled color are: (a) to maintain a uniform assimilation of moisture (see discussion of moisture); (b) to strain the starter to break up the lumps before adding to the milk; (c) to add all of the starter before adding the cheese color; (d) not to mix curds from different vats.

Seamy color.—In "seamy" colored cheese, the outline of each piece of curd may be seen. There is usually a line where the surfaces of the curd come together. It may be caused by the pieces of curd becoming greasy or so cold that they will not cement. This may be remedied by having the curd at a temperature of 80° to 85° F. when put to press. If it is greasy, this may be removed by washing the curd in cold water.

Acid color.—This is a bleached or faded color and is caused by the development of too much acid. (See acid flavor for causes and remedies, [page 266.])

261. Defects in finish.—Defects of this class differ from those previously mentioned in being entirely within the control of the cheese-maker. All are due to carelessness or lack of skill in manipulation. Anything which detracts from the neat, clean, workmanlike appearance of the cheese is a defect that may interfere with the sale of an article intrinsically good. Some of the common defects are: (a) unclean surfaces or dirty cheese; (b) cracked rinds; (c) moldy surfaces; (d) uneven sizes; (e) cracked cheese; (f) wrinkled bandages; (g) uneven edges.