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"
Constituent quark Constituent quark A constituent quark is a current quark with a notional "covering" induced by the renormalization group. In the low energy limit of QCD, a description by means of perturbation theory is not possible: Here, no asymptotic freedom exists, but collective interactions between valence quarks and sea quarks gain strongly in significance. Part of the effects of virtual quarks and virtual gluons in the 'sea' can be assigned to a quark so well, that the term 'constituent quark' can serve as an effective description of the low energy system. Constituent quarks appear like 'dressed' current quarks, i.e. current quarks