Butter as Sauce: Melted Butter, Beurre Noisette, and Beurre Noir Perhaps the simplest of sauces is the pat of butter dropped on a heap of hot vegetables, or stirred into rice or noodles, or drawn across the surface of an omelet or steak to give a sheen Melted butter can be enlivened with lemon juice, or “clarified” to remove the milk solids (see bel ow) Beurre noisette and beurre noir, “hazel” and “black” butter, are melted butter sauces that the French have used since medieval times to enrich fish, brains, and vegetables Their flavor is deepened by heating the butter to about 250ºF/120ºC until its water boils off and the molecules in the white residue, milk sugar and protein, react with each other to form brown pigments and new aromas (the browning reaction, p 777) Hazel butter is cooked until it’s golden brown, black butter until it’s dark brown (truly black butter is acrid) They’re often balanced with vinegar or lemon juice, which should be added only after the butter has cooled below the boiling point; otherwise the cold liquid will cause spattering and the lemon solids may brown On their own, they lend a rich nutty flavor to baked goods The emulsified butter sauces — beurre blanc, hollandaise, and their relatives — are described in chapter 11 Clarified Butter Clarified butter is butter whose water and milk solids have been removed, leaving essentially pure milk fat that looks beautifully clear when melted and that is better suited for frying (the milk solids scorch at relatively low frying temperatures) When butter is gently heated to the boiling point of water, the water bubbles to the top, where the whey proteins form a froth Eventually all the water evaporates, the bubbling stops, and the froth dehydrates This leaves a skin of dry whey protein on top, and dry casein particles at the bottom Lift off the ...only after the butter has cooled below the boiling point; otherwise the cold liquid will cause spattering and the lemon solids may brown On their own, they lend a rich nutty... where the whey proteins form a froth Eventually all the water evaporates, the bubbling stops, and the froth dehydrates This leaves a skin of dry whey protein on top, and dry casein particles at the bottom... melted and that is better suited for frying (the milk solids scorch at relatively low frying temperatures) When butter is gently heated to the boiling point of water, the water bubbles to the top,