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 routinely used in medical applications such as positron emission tomography (PET) and in experiments involving neutrino detection. While the process of flavor transformation is the same for all quarks, each quark has a preference to transform into the quark of its own generation. The relative tendencies of all flavor transformations are described by a mathematical table, called the Cabibbo–Kobayashi–Maskawa matrix (CKM matrix). Enforcing unitarity, the approximate magnitudes of the entries of the CKM matrix are: where "V" represents the tendency of a quark of flavor "i" to change into a quark of flavor "j" (or vice versa). There exists an