According to its namesake, it all starts with the fish. Phung Hung, a producer on the island of Phú Quốc, sources his supplies with his fleet of fishing boats, but not all manufacturers do. Immediately after a catch of mostly cá cơm (black anchovies), the fish is drained and salted, which triggers fermentation before the boat reaches shore. Then it is loaded into wooden barrels, where it is kept for a full year. The resulting sauce is slowly drained and added back, but never stirred. Ongoing taste testing determines when it’s ready, according to CNN Travel.
Not all fish sauces are made the same way. Small family growers buy a mix of small fish at a market and use rows of outdoor ceramic containers, rather than wooden barrels. They layer the fish and salt and stir once the fermentation begins. The process is time consuming – the ceramic tubs have to be moved indoors when it rains. Once a salt crust develops, from five days to four weeks, the result is sifted and sometimes aged, by Vietnam Jeep Tours.
Less stirred sauces produced in Phú Quốc are often called “extra virgin” and considered the best in the world for their sweet finish, according to Our Daily Brine. However, each producer offers their own unique palate of flavors – perfect for experimenting with when cooking classic Vietnamese dishes.