Quark (dairy product) these products are obtained by straining yogurt (milk fermented with thermophile bacteria), quark is made from soured milk fermented with mesophile bacteria. Quark is possibly described by Tacitus in his book "Germania" as "lac concretum" ("thick milk"), eaten by Germanic peoples. However, this could also have meant soured milk or any other kind of fresh cheese or fermented milk product. Although quark is sometimes referred to loosely as a type of "cottage cheese", they can be distinguished from the different production aspects and textural quality, with the cottage cheese grains described as more chewy or meaty. The word "Quark" (Late
Quark model Quark model In particle physics, the quark model is a classification scheme for hadrons in terms of their valence quarks—the quarks and antiquarks which give rise to the quantum numbers of the hadrons. The quark model underlies "flavor SU(3)", or the "Eightfold Way", the successful classification scheme organizing the large number of lighter hadrons that were being discovered starting in the 1950s and continuing through the 1960s. It received experimental verification beginning in the late 1960s and is a valid effective classification of them to date. The quark model was independently proposed by physicists Murray Gell-Mann, and George Zweig (also