Ouzo alcohol at approximately 38% ABV and above, but not in water. Diluting the spirit causes it to separate creating an emulsion, whose fine droplets scatter the light. This process is called louching, and is also found while preparing absinthe. Similar aperitifs include oghi (from Armenia), mastika from Bulgaria and Macedonia, rakı from Turkey, pastis (France), and arak (from the Levant). Its aniseed flavour is also similar to the anise-flavoured liqueurs of sambuca (Italy) and anís (Spain) and the stronger spirits of absinthe (France and Switzerland). Aguardiente (Colombia), made from sugar cane, is also similar. The Italian drink "Pallini Mistra," named
Flavour (particle physics) violated by weak interactions. Therefore, such flavour quantum numbers are not of great use. A separate quantum number for each generation is more useful: electronic lepton number (+1 for electrons and electron neutrinos), muonic lepton number (+1 for muons and muon neutrinos), and tauonic lepton number (+1 for tau leptons and tau neutrinos). However, even these numbers are not absolutely conserved, as neutrinos of different generations can mix; that is, a neutrino of one flavour can transform into another flavour. The strength of such mixings is specified by a matrix called the Pontecorvo–Maki–Nakagawa–Sakata matrix (PMNS matrix). All quarks carry a