Ouzo it is generally considered poor form to drink ouzo "dry hammer" ("ξεροσφύρι", "xerosfýri", an idiomatic expression that means "drinking alcohol without eating anything") in Greece. The presence of food, especially fats or oils, in the upper digestive system prolongs the absorption of ethanol and ameliorates alcohol intoxication. Ouzo is not used in many mainstream cocktail drinks, although in Cyprus it does form the basis of a cocktail called an Ouzini. Ouzo is a clear liquid. However, when water or ice is added, ouzo turns a milky-white colour. This is because anethole, the essential oil of anise, is completely soluble in
Flavour (particle physics) basis to the flavor-eigenstate/mass-eigenstate basis for quarks underlies the Cabibbo–Kobayashi–Maskawa matrix (CKM matrix). This matrix is analogous to the PMNS matrix for neutrinos, and quantifies flavour changes under charged weak interactions of quarks. The CKM matrix allows for CP violation if there are at least three generations. Flavour quantum numbers are additive. Hence antiparticles have flavour equal in magnitude to the particle but opposite in sign. Hadrons inherit their flavour quantum number from their valence quarks: this is the basis of the classification in the quark model. The relations between the hypercharge, electric charge and other flavour quantum numbers hold