Ristretto is traditionally a short shot of espresso coffee made with the normal amount of coffee but extracted with about half the amount of water. Since ristrettos are essentially the first half of a full length extraction, the faster-to-extract compounds predominate in a ristretto. The opposite of a ristretto is a lungo, which is typically doubl...Found on http://en.wikipedia.org/wiki/Ristretto
This is the strongest and most concentrated espresso drink. It is made with about half the amount of water but the same amount of coffee as a regular espresso. It is pure and intense. Ristretto in Italian means 'restricted'.
Found on http://www.realcoffee.co.uk/Article.html?Cat=Trivia&Page=4
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