When trying out Southeast Asian recipes, there is one key ingredient that you can’t skip. Yes, you get it right, fish sauce!
It’s been months since the first time you opened a bottle of fish sauce since most recipes usually only call for a small amount of it. Now, the same bottle is still half full, sitting at the back of the refrigerator.
At this point, you’re asking yourself whether the fish sauce is still okay to use? Does fish sauce go bad?
Whether you are new to fish sauce or have been using it for a while, in this article we’ll tell you the basics of fish sauce: shelf life, how to store, and how to tell if fish sauce is bad. Interested? Read on!
What Is Fish Sauce?
Fish sauce is a staple ingredient in Southeast Asian and East Asian cuisines. Fish sauce is made by fermenting fish, mostly anchovies, and salt for at least 12 to 18 months.
The fermentation process produces a liquid with a salty and savory flavor that will elevate the taste of your curry, stews, stir-fry, and whatnot.
Thailand and Vietnam are major producers of fish sauce. Due to its authenticity and quality, fish sauce produced in Phu Quoc, Vietnam receives an EU trademark on geographical indication (PDO).
Depending on the brands and quality, some ingredients may be added with sugar, preservatives, monosodium glutamate, etc. Premium quality fish sauce is only made with fish and salt, without any preservatives or food additives.
Although fish sauce owes its origin to Asian cooking, nowadays this source of umami taste is also embraced by a wider community, that’s probably including you.
Fish sauce adds a unique, distinctive taste to your marinades, dipping sauces, and salad. The bottom line is, fish sauce boosts a rich flavor to any savory dishes.
How To Store Fish Sauce
When it comes to storing fish sauce, it is similar to Worcestershire sauce or soy sauce. As long as the bottle is unopened, you can keep it in a cool, dry environment, away from sources of heat and sunlight. Your pantry or cupboard is the ideal place.
The most common question about storing fish sauce is whether to refrigerate it or not. Depending on the brand or quality and how frequently you use it, after opening you can store fish sauce either inside or outside the refrigerator. Either way, always keep the bottle tightly sealed after use.
Once opened, the flavor and taste will slowly deteriorate. If you don’t use it quite often, better to refrigerate it to slow down the process and you can keep it fresh for much longer.
Premium quality usually doesn’t contain preservatives, while the lesser quality does. Preservative makes the fish sauce more stable to store at room temperature after opening. Check the label for precise storage instruction.
Fish sauce won’t go bad instantly when not refrigerated, thanks to the amount of salt in it. In the Asian kitchen, it is quite common to leave fish sauce outside the fridge since it’s used very frequently if not daily.
How Long Does Fish Sauce Last?
Fish sauce bottles come with a “best-before” or “best-use-by” date. First and foremost, consult this information for your purchase and consumption.
Fish sauce has a stable shelf life and typically lasts for quite some time, on average 3 to 4 years. According to Red Boat Fish Sauce, one of the major premium fish sauce producers in the US, fish sauce lasts for 36 months after the manufacturing date. Of course, the shelf life may be extended beyond this period, subject to proper storage.
After opening, the flavor and taste will start to degrade slowly over time. When stored in the refrigerator, it can stay fresh of up to a year. But, when left in the cupboard or at room temperature, better to use it within 3 to 6 months.
If you only use fish sauce occasionally, it is recommended to buy a small bottle. This way you can always enjoy the freshness until the last drop of the sauce before it loses the quality. Old fish sauce is more suitable for cooking, while the new one is great for condiment or sauce.
How To Tell If Fish Sauce Has Gone Bad
Fish sauce rarely goes bad to a point that it will make you sick. The high amount of salt is likely unfavorable from bacterial growth.
However, the flavor and taste may decline over time. At some point, you may want to discard the product for quality reasons.
When you pour fish sauce for the first time, you can see that the color is golden, brownish, and clear. After a while, it may get darker and crystals may form in the bottle. The crystals are salts and shouldn’t be a concern. The darker color is normal since the sauce aged.
But, if fish sauce develops off-smell that’s distinctively different from the first time you opened the bottle, you should consider discarding it. Likewise, if molds grow on the lid or surface of the bottle.
FAQs
No, oyster sauce is not a similar product to fish sauce. Although both are staples in Asian cooking, they have different characteristics and use. Be sure to check the recipe to not get confused.
Traditionally, fish sauce is made with anchovies and salt. Shrimp is not a common ingredient. Usual addition includes sugar, monosodium glutamate, and preservatives.
But, just to be sure, check the ingredients lists for more detailed information.
Fish sauce does smell somewhat ‘fishy’, especially if you’re not familiar with it. Hang on there, don’t be deterred by the smell. Once you add a dash or two into the recipe, you’ll be blown away by the rich flavor it creates.
But, if the smell is different from the first time you opened the bottle, the fish sauce may have degraded.
When you only use fish sauce occasionally or are in search of a vegan substitute, you can opt for soy sauce. Although the depth of flavor from the fish sauce is hard to replace, soy sauce works pretty well for most recipes.
Summary
Fish sauce is a key ingredient to many Asian recipes. Fish sauce has a stable shelf life and is very rare to go bad, thanks to the amount of salt in it. But, the flavor and taste deteriorate slowly over time.
Whether to refrigerate it or not, that depends on the brand and your frequency of use. But, either way, always tightly seal the cap. If you want to keep the fish sauce for a longer time, it is recommended to always keep it refrigerated.

*Photo by luknaja/depositphotos