Monday, February 11, 2013

The Digestibility of Cheese

From "The Book of Cheese", 1918.

Although it has been a staple food with many races for uncounted years, there is a widespread belief that cheese is suitable for use chiefly in small quantities as an accessory to the diet, and that in large quantities it is likely to produce physiological disturbances. The question of digestibility was made the subject of a special investigation by the United States Department of Agriculture.

Calorimeter experiments were made to test the digestibility of several varieties of cheese and some of these varieties at various stages of ripening. All forms of cheese were found to be digested as completely as most of the usual forms of food. Approximately 90 per cent of the nitrogenous portion (casein) was retained in the body. Unripe cheese in these experiments was apparently digested as completely as the ripened forms.

These experiments make clear the possibility of making cheese a more prominent article in the regular dietary than is usual in America. They especially point to the desirability of the use of the skim and partially skim cheeses, which as cheap sources of protein when properly combined with other foods, may be made to replace meats as a less costly source of proteins.

Cheese is then to be classed with meat and eggs, not with condiments. An ounce of Cheddar cheese roughly is equivalent to one egg, to a glass of milk, or to two ounces of meat. It is properly to be combined with bread, potatoes and other starchy foods, lacking in the fat in which the cheese is rich.

These experiments included Roquefort, fresh-made and ripe Cheddar, Swiss, Camembert and Cottage cheese.

Sunday, February 10, 2013

French Camembert

The soft cheeses ripened by molds are French in origin. Their manufacture has spread into Germany, Italy and America. Of the series, the most widely known is Camembert, which will be described as typical for the group. Brie, Coulommiers, Robbiola and Ripened Neufchâtel belong to this series.

The origin of Camembert is given by French authorities as 1791 in the Commune of Camembert near Vimoutiers in Orne, France. From a very restricted production at first, Camembert-making has spread through the region from Caen in the west to Havre, Rouen and a considerable area east of Paris.

In America Camembert began to be made in one factory about 1900. Several other factories followed by 1906. The difficulties and losses encountered led to the abandonment of these undertakings, until at the outbreak of the European war in 1914 but one factory was making Camembert and that only on an experimental scale. Meanwhile the United States Department of Agriculture and the Storrs Experiment Station had taken up and solved, on an experimental basis, most of the problems arising in these commercial failures. A shortage of product at the outbreak of the war brought about the re-establishment of a series of factories. The product as put on the market indicates that a permanent establishment of Camembert-making is entirely practicable.

Camembert cheese is made from cow's milk either whole or very slightly skimmed; the removal of about 0.5 per cent of fat has been found to be desirable if not actually necessary.

These cheeses are made in sizes 2½ to 4½ inches in diameter and 1¼ to 1½ inches in thickness. They are ripened by the agency of molds and bacteria which form a felt-like rind over their whole surface, ⅟16 to ⅛ of an inch in thickness. This rind may be dry and gray or grayish-green, consisting of a felt-like surface of mold on the outside, below which a harder portion consists of mold embedded in partially dried cheese, or the moldy part may be more or less completely overgrown or displaced by yellowish or reddish slime composed mainly of bacteria. Good cheeses may have either appearance.

Inside the rind, the cheese is softened progressively from the rind toward the center from all sides, so that a fully ripe cheese has no hard sour curd in the center, but is completely softened. No mold should be visible inside the rind, but the moldy rind itself is necessary because the ripening is caused by the enzymes secreted by the organisms of the rind into the cheese. As the curd ripens, the changed portion assumes a slightly deeper color than the unripe curd as a result of chemical changes.

Well-ripened cheeses vary from nearly a fluid texture to the consistency of moderately soft butter. The ripening of Camembert is finished in wooden boxes which protect the cheeses from breaking after they become soft and during the market period.

Saturday, February 9, 2013

The Water Content of Different Cheeses

From "The Book of Cheese", 1918.

In this table the series of typical dairy products are first arranged according to water-content of the final product. Approximate limits of percentages of milk-fat are also given, because milk-fat frequently affects texture to a degree almost equal to water. Column 4 gives the period within which the more quickly perishable cheeses are usable, and the length of the ripening for the more solid forms. The correlation between water-content, texture and the time of keeping is clearly shown for most varieties.

Variety Per

  Cottage 70 trace a few days Bacteria
  Skim Neufchâtel 70 trace a few days Bacteria
  Neufchâtel 50-60 12-28 a few days Bacteria
  Camembert 50 22-30 3-5 weeks Molds
  Cream cheese 40-50 35-45 a few days Primarily
  Limburger 40-45 24-30 3-6 months Bacteria
  Roquefort 38-40 31-34 3-6 months Mold
  Brick 37-42 31-35 3-6 months Bacteria
  Cheddar 30-39 32-36 6-12 months Bacteria
  Swiss 31-34 28-31 9-18 months Bacteria
and yeasts
  Parmesan 30-33 2-3 years Bacteria

The soft cheeses are quickly perishable products. Bacteria and molds find favorable conditions for growth in products with 45 to 75 per cent of water. If such growth is permitted, enzymic activities follow quickly with resultant changes in appearance, texture, odor and taste. Refrigeration is necessary to transport such cheeses to the consumer, if properly ripened. Trade in these forms may continue throughout the year in cool climates and in places where adequate refrigeration is available. Practically, however, outside the large cities this trade in America is at present limited to the cold months; inside the large cities much reduced quantities of these cheeses continue to be handled through the year.

In the stricter sense, the soft group of cheeses falls naturally into two series: (1) the varieties eaten fresh; and (2) the ripened soft cheeses. Those eaten fresh have a making process which commonly involves the development of a lactic acid flavor by souring, but no ripening is contemplated after the product leaves the maker's hands. In the ripened series, after the making process is completed, the essential flavors and textures are developed by the activity of micro-organisms during ripening periods varying in length but fairly well-defined for each variety.

In contrast to the soft cheeses, the hard kinds are low in water-content, ripen more slowly and may be kept through much longer periods. They retain their form through a wider range of climatic conditions. They develop flavor slowly and correspondingly deteriorate much more slowly. Such cheeses are in marketable condition over longer periods. In their manufacture the cooking of the curd takes a prominent place.