Is Your Fish Sauce Fresh?
It may sound like a risqué or saucy question, but it is at the heart of making truly delicious Thai food at home. You must have the finest ingredients, including bottled sauces. Fresh fish sauce has a briny, seawater like scent and has a clean taste full of salty and savory flavors. But fish sauce that has gone stale smells and tastes terrible and will ruin your carefully thought out meal.
Fish sauce is made from mixing anchovies, salt and water in a receptacle and letting the mixture mature for up to a year. Then the amber colored liquid is filtered, pasteurized and put into bottles for shipping. It is a mainstay of Thai cooking similar to the role soy sauce plays in Chinese cooking.
By the way, you know as a farang you have gone way too “native” in Thailand when you think a bowl of steamed jasmine rice with a few shots of fish sauce mixed in is a meal. But for many Thai folks this simple meal would be enough. That is how treasured fish sauce is to Thai eaters.
But, fish sauce ages and decays in the bottle over time. The rotten fish sauce tastes bad and overly salty and smells terrible, You can see in the photo that the fish sauce on the left has turned a harsh dark color; the fresher fish sauce on the right is still a paler tea color. This rancid old fish sauce should be disposed of with the same care one would take with radioactive waste due to its nasty smell. If you spill this old fish sauce in your car, you would have to burn the car. The car would have no resale value due to the penetrating and lingering stench. Trust me, it is a fact.
The challenge with fish sauce is that it is made and bottled at a specific location, and then must be sent by ship to America or Europe, etc. Upon arrival, it is distributed to the supermarkets and speciality stores around the country. Thus there is a several month time lag between shipping and its sale.
The good news is many commercial fish sauce brands exported from Thailand have a manufacture date and an expiration date printed on the bottle cap or label. So you can use the manufacture date as a guideline to purchasing the fish sauce most recently made. You can use your own judgement and discard any fish sauce that has changed color from whiskey color to black – that is the first sign it has aged too much to be used by a discerning chef.
My favorite brands? Tiparos, Golden Boy and Tra Chang (Weighing Scale) are preferred.