Quark (dairy product) as the Vermont Creamery in Vermont, and some specialty retailers carry it. Lifeway Foods manufactures a product under the title "farmer cheese" which is available in a variety of metropolitan locations with former Russian populations. Elli Quark, a Californian manufacturer of quark, offers soft quark in different flavors. In Canada, the firmer East European variety of quark is manufactured by Liberté Natural Foods; a softer German-style quark is manufactured in the Didsbury, Alberta, plant of Calgary-based Foothills Creamery. Glengarry Fine Cheesemaking in Lancaster (Eastern Ontario) also produces Quark. Also available in Canada is the very similar "Dry Curd Cottage Cheese"
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