Quark

Quark is a type of fresh, also known as tvorog (from the творог), topfen (from the  name), biezpiens (from ), and varškė (from ). It is made by warming soured milk until the desired degree of denaturation of milk proteins is met, and then strained. Dictionaries usually translate it as curd cheese or cottage cheese, although most commercial varieties of cottage cheese are made with rennet, whereas traditional quark is not. It is soft, white and unaged, similar to some types of fromage frais. It is distinct from ricotta because ricotta (Italian: recooked) is made from scalded whey. Quark usually has much lower fat content (about the same as ) than cream cheeses and has no salt added.

In Germany, quark is sold in small plastic tubs and usually comes in two different varieties, Magerquark (lean quark) and Sahnequark (cream quark) with added cream. While the former is often used for baking and as health food, e.g. as a breakfast spread, the latter also forms the basis of a large number of quark desserts. Much like yoghurts in most parts of the world, these treats mostly come with fruit flavouring (Früchtequark, fruit quark), and are often also simply referred to as quark. As the large popularity of quark desserts is limited to mainly the German-speaking countries, confusion might arise when talking about quark with people unfamiliar with the German or the Austrian cuisine.

Name
The name comes from the Late Quark, which in turn is derived through twarc, quarc, zwarg from the   tvarog, ( twaróg,  тварог,  творог, and  and  tvaroh, which means "curd". In, the name Topfen (pot cheese) is used, and in Hungarian, túró is used. In , it is called platte kaas (flat cheese), while the Dutch use the name kwark. In ,  and , it is called kvarg. However, in  it is more commonly known under the product name "Kesella".

The cheese is also known simply as "white cheese" (Polish: ser biały, Baltas sūris}}, southern Germany: Weißkäse or weißer Käs, Hebrew: Gvina Levana גבינה לבנה), as opposed to any rennet-set "yellow cheese".

In it is known as túró, in  it is known as rahka, while in  as kohupiim (foamy milk). The French-language word for it is seré, but it is most commonly called fromage blanc.

Quark is possibly described by  in his book  as lac concretum (thick milk), eaten by.

Production
Quark is a member of the acid set cheese group, meaning it is traditionally made without the aid of rennet. In most German dairies today, it is made with rennet. are added in the form of  starter cultures. Acidification continues until the reaches 4.6, which causes precipitation of the casein proteins. In Germany, the curd is continuously stirred to prevent it from getting hard, resulting in a thick, creamy texture. Quark is usually sold in plastic tubs with most or all of the whey. This type of quark has the firmness of but is slightly drier, resulting in a somewhat crumbly texture (like American ricotta), and contains in its basic form about 0.2 % fat. Quark with higher fat content is made by adding cream, and is often sold flavored with herbs, spices, or fruit. It has a very smooth and creamy texture and is slightly sweet (unlike sour cream).

To make the firmer eastern European version, a small amount of rennet may be added to make the curd firmer. Some or most of the whey is removed to standardize the quark to the desired thickness. Traditionally, this is done by hanging the cheese in loosely woven cotton called  and letting the whey drip off, which gives quark its distinctive shape of a wedge with rounded edges. In industrial production, however, cheese is separated from whey in a and later formed into blocks. The Polish, and  varieties contain less whey and are therefore drier and more solid than varieties common in other countries.

Quark consists of 60% to 80% water. has 1% to 40% ; most of the rest is (80% of which is casein),, and.

Applications
Quark is often used as an ingredient for, , and cheesecake, called Käsekuchen or Quarkkuchen in Germany, Quarktorte in , Topfenkuchen in Austria, "kwarktaart" in the , vatrushka in , tvarohovnik in  and , and sernik in. In these cakes, the quark is typically mixed with, milk or , and , and. A firmer variant, called Schichtkäse (layer cheese) is sometimes used for Käsekuchen. Quark flavored with or fruit is used as a dessert in    and Germany. In German, this is called Quarkdessert. In Poland, twaróg is mixed with mashed potatoes to produce a popular filling for . In and Russian-speaking countries, quark, known as tvorog ( творог), is highly popular and is bought frequently by almost every family. As a result, tvorog is a member of the official minimal basket of foods. In Russian families, it is especially recommended for growing babies. It could be simply enjoyed with sour cream, or jam, sugar, sugar condensed milk. It is often used as a stuffing in crepes purchased at many fast-food restaurants. It is also commonly used as the base for making Easter cakes. It is mixed with, , , and and dried into a solid pyramid-shaped mass. The mass can also be, then known as syrnik (served with sweets).

Availability
Although common in Europe, manufacturing of quark is rare in the. A few dairies manufacture it, and some specialty retailers carry it. Lifeway(Morton Grove, IL ) manufactures a product under the title "" which is available in a variety of metropolitan locations with former Russian populations. Quark is also available at several upstate NY farms. In Canada, quark (firmer East European variety) is manufactured in Quebec by Liberté and may also be available as "baking cheese" or fromage frais.

In India, the Amul co-operative dairy products company sells Shrikhand and labels it as quark.

The Israeli variety, Gvina Levana (גבינה לבנה, white cheese) can be found in most households and is an integral part of the Israeli breakfast (and often, of supper). It has a more neutral and delicate taste, and it contains between 3% and 9% percent fat, 5% and 9% are the most popular. The Russian quark was introduced to Israel during the by immigrants from the former Soviet Union, and is now available under the name tvorog.

In Australia, it is sometimes available from supermarkets labelled as quark.

Cooking
Quark is commonly used for cooking. Various cuisines, especially cuisines of former-USSR countries (e.g. Russia, and ) feature quark as an ingredient for appetizers, salads, main dishes, side dishes and desserts.