Does Fish Sauce Go Bad? Where Should I Store It?

logo by Editorial Staff | Updated on December 22nd, 2022

You just discovered a half-opened bottle of fish sauce. You purchased it, used it a few times, and then put it away. It’s been a few months, and you’re unsure if you can still use it. Is it possible for fish sauce to spoil?

What Is Fish Sauce?

Fish sauce is a common element in Southeast and East Asian cuisines. Fish sauce is produced by fermenting fish, primarily anchovies and salt, for at least 12 to 18 months.

fish sauce

The fermentation process results in a salty and delicious liquid that will enhance the flavor of your curries, stews, stir-fry, and other dishes.

Thailand and Vietnam are two of the world’s largest fish sauce manufacturers. Fish sauce manufactured in Phu Quoc, Vietnam, has been granted an EU geographical indication trademark due to its authenticity and excellence.

What Are the Ingredients in Fish Sauce?

Certain components may contain sugar, preservatives, monosodium glutamate, and other additives, depending on the brand and quality. A high-quality fish sauce is composed only of fish and salt, with no preservatives or food additives.

What Does Fish Sauce Taste Like?

Although fish sauce originated in Asian cuisine, this source of umami flavor is now enjoyed by a broader audience, which most likely includes you.

Fish sauce gives a particular flavor to marinades, dipping sauces, and salads. To summarize, the fish sauce adds a deep taste to any savory food.

This is a regular occurrence, especially with condiments like fish or oyster sauce. You purchase a bottle because a recipe you’d want to attempt asks for it. You create the recipe once or twice, then store it in a half-opened bottle for months.

Of course, fish sauce has a variety of applications in Southeast and East Asian cuisine, where it is a mainstay. But unless you’re into that cuisine or do some recipe research, you probably don’t realize there are a lot of uses for fish sauce. That’s OK.

This page will discuss the storage, shelf life, and spoilage of this condiment created from fermented fish. Continue reading if you want to understand more about fish sauce.

How Long Will Fish Sauce Last?

Many fish sauce bottles have a best-by date. This date tells you how long the product will keep its freshness and taste. Of course, because the ish sauce has no perishable components and is heavy in salt, it may easily be stored for months or even years after the expiration date. As a result, some producers do not include dates on the label other than bottling dates.

Even though fish sauce seldom goes bad regarding food safety, its quality deteriorates with time. That implies that after a lengthy period of storage, you may notice that the flavor is weaker and the taste is absent.

It’s hard to predict when this will happen, especially because you’re the one who decides it’s not good enough to utilize.

Fish sauce and oyster sauce are not the same things. There are some similarities. However, they are two different items.

Let us now discuss temporal periods. An unopened bottle of fish sauce should easily last a year after the best-by date or 3-4 years after bottling in good condition. An opened bottle of refrigerated fish sauce should keep its quality for at least a year. Of course, it will likely retain its freshness for considerably longer.

Fish sauce (unopened)Best by + 1 year 
Fish sauce (opened)3 – 6 months12+ months

Why Does Fish Sauce Have an Expiration Date?

Although there is no legal necessity in the United States for fish sauce to include an expiration date, most producers include one since consumers are likelier to believe items that tell us when they should be thrown. These dates are typically three to four years after the manufacturing date, which is conservative compared to industry requirements. The condiment has a five-year shelf life, according to the Handbook of Indigenous Fermented Foods in ASCA Countries (published by the Association for Science Cooperation in Asia, a science-policy group).

How Can You Tell If Your Fish Sauce Is Bad?

As previously said, fish sauce is unlikely to spoil, but you should always inspect it before storing it for an extended period.

Even though producers provide best-by dates on the bottle label, there are no regulatory regulations in the United States addressing the expiration date of fish sauce. Customers who rely on food with an expiration date are at risk.


Clear crystals can frequently be seen on the bottom of fish sauce bottles. It is not a symptom of deterioration, and the sea salt crystals in this sauce develop naturally over time. The best thing is that they will not affect the sauce’s quality.

Cloudy particles

Proteins are little hazy particles floating in the container. They precipitate when the fish sauce is stored in an area with large temperature changes. It is a natural procedure that does not affect the taste of the sauce.


The hue of fresh fish sauce is translucent, golden-brownish, and reddish-brown, with no sediment. Be aware that this product will darken over time but will not impact its quality or taste.


The flavor of the fresh sauce is reminiscent of delicious fish. Some dislike the fishy stench. However, it fades quickly when added to a dish. In truth, this condiment has a deep flavor that you will like. When a product gets bad, it emits a terrible stench. That is a solid indicator that the product is no longer edible.


You can sample a bite if you determine that your fish sauce looks and smells OK, but you are still unclear if it is useful. If the taste is noticeably different from the fresh goods you purchased, it is best to discard it.


It’s not often, but you can occasionally detect mold growing inside a bottle cap. It is time to discard the entire bottle if you notice mold, even in traces on the sauce’s surface.

The Dangers of Eating Expired Fish Sauce

When you eat food beyond its expiration date, you might anticipate symptoms of food poisoning, followed by common symptoms such as fever, stomachache, nausea, vomiting, and diarrhea.

Fish sauce, on the other hand, is something special. Due to the manufacturing process and high salt levels, this product will not go bad for years, and its taste will remain intact.

Preservatives such as salt will keep it from rotting, and you will not suffer any bad repercussions even if you eat an old condiment preserved in its original box.

How Do You Store Fish Sauce?

Keeping fish sauce is akin to keeping teriyaki or soy sauce. You may keep it in the pantry or kitchen at room temperature or slightly below, as long as the bottle is unopened. Make sure it’s away from sources of light and heat, as they might degrade the sauce’s quality.

Once you’ve opened the bottle, ensure it’s always firmly sealed when it comes to storing it after opening, Keeping it in the fridge for the greatest quality.

Because it includes a lot of salt, it won’t go bad if you leave it at room temperature for a day or a week. Or, for that matter, a month.

On the other hand, chilling it in the fridge will help it keep its quality for longer, so where you store it is entirely up to you.

If you plan to keep the sauce for longer than 6 months, I recommend storing it in the refrigerator. For shorter periods, the pantry should suffice.

Is It Possible to Freeze Fish Sauce?

You cannot and should not freeze the fish sauce. It’s that easy, so there’s no need to keep this product in the freezer because it comprises fish and salt. Salt is a preservative that destroys microorganisms and keeps this food safe to consume for an extended time.

Food cannot deteriorate in the absence of these microbes. As a result, storing this condiment in a pantry or refrigerator for months, if not years, will suffice.


Is oyster sauce similar to the fish sauce?

No, oyster sauce is not the same as fish sauce. Although both are common ingredients in Asian cuisine, they have distinct features and applications. To avoid confusion, double-check the recipe.

Is the fish sauce made with shrimp?

Traditionally, anchovies and salt are used to make fish sauce. Shrimp is a unique ingredient. Sugar, monosodium glutamate, and preservatives are common additions.

However, for more specific information, see the component lists.

Is fish sauce unpleasant to the senses?

Fish sauce has a ‘fishy’ scent, especially if you’re unfamiliar with it. Hold on, don’t be put off by the odor. You’ll be taken away by the rich taste it generates after you add a dash or two to the mix.

However, if the fragrance differs from when you originally opened the container, the fish sauce may have deteriorated.

What are some (vegan) alternatives to the fish sauce?

If you use fish sauce occasionally or are looking for a vegan equivalent, soy sauce is a good option. Although the depth of flavor provided by fish sauce is difficult to replicate, soy sauce works well in most dishes.


Editorial Staff

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