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 and top quarks) can change into any down-type quark (down, strange, and bottom quarks) and vice versa. This flavor transformation mechanism causes the radioactive process of beta decay, in which a neutron () "splits" into a proton (), an electron () and an electron antineutrino () (see picture). This occurs when one of the down quarks in the neutron () decays into an up quark by emitting a virtual boson, transforming the neutron into a proton (). The boson then decays into an electron and an electron antineutrino. Both beta decay and the inverse process of "inverse beta decay" are