Fish sauce is often made from anchovies, salt, and water, and is intensely flavoured. Anchovies and salt are arranged in wooden barrels to ferment and are slowly pressed, yielding the salty, fishy liquid. The salt extracts the liquid via osmosis. Southeast Asians generally use fish sauce as a cooking sauce. However, there is a sweet and sour version of this sauce which is used more commonly as a dipping sauce (see "nước chấm"). Fish sauce in Burma is called "ngan bya yay" (ငံပြာရည်). In Cambodia, fish sauce is known as "teuk trei" (ទឹកត្រី), of which there are a variety of sauces using
Fish sauce briefly fermented has a pronounced fishy taste. Extended fermentation reduces this and gives the product a nuttier, richer and more savory flavor. An anonymous article, "Neuc-num", in Diderot and d'Alembert's 18th-century Encyclopédie, states: "It is said that Europeans become accustomed enough to this type of sauce". While there is no strict grading system for fish sauces, first-tapping, or first-pressing sauces are the most sought after. Some top brands are beginning to adopt the "Extra Virgin" designation and tout more artisan processes. Second-pass or volume sauces are easily identified as they have a thin, very watery consistency. Southeast Asian fish sauce