What happens if you eat expired oyster sauce? (+5 Tips)

In this article, we will answer the question “What happens if you eat expired oyster sauce?”, and how to tell If the oyster sauce is bad?

What happens if you eat expired oyster sauce?

Oyster sauce does not become unsafe for consumption past its expiry If it’s stored correctly. It loses its flavor and intensity past the expiration date and may or may not cause food poisoning.

The symptoms of food poisoning may vary from person to person and with the virulence of the mold or bacteria ingested. Common symptoms include headache, nausea, weakness, mild fever, loss of appetite, vomiting, diarrhea, and stomach cramps. 

These symptoms should go away in 1-2 days. If they don’t go away or become intense, consult a doctor. Severe symptoms might include bloody urine, extreme dehydration due to diarrhea, fever above 101.5℉, and diarrhea that persists for more than 3 days.

Does oyster sauce go bad?

How to tell If the oyster sauce is bad?


Mold growth on the surface of the sauce or around the cap is an obvious indication of spoilage. Do not try to use the rest of the oyster sauce by removing the moldy part. It does not work like that. Discard it immediately because safety first!

Color and flavor 

As time passes, the oyster sauce develops a deeper color and a more intense flavor due to the oxidation.


Oyster sauce should have a balanced sweet and sour flavor with hints of caramel flavor to it. If it tastes too sour or has a bitter aftertaste, It has gone bad.


If the oyster sauce gives off a rotten or moldy smell instead of its fresh smell, discard it immediately.


Ideally, the oyster sauce should have a thick consistency much like a thick broth. If it feels too watery when poured out, It has gone bad.

Other FAQs about Sauces which you may be interested in.

What happens If you eat expired sauce?

How long does the oyster sauce last?

The shelf-life of the oyster sauce depends upon its initial quality and its storage. Thus It varies from brand to brand. 

An unopened bottle of oyster sauce will last about 18-24 months depending upon the production quality and storage practices. 

The printed date on the bottle of the sauce will give you a rough estimation of how long the sauce will retain its prime quality. 

A high-quality oyster sauce will retain its freshness for up to a year after its opening. On average, the shelf-life of opened oyster sauce is anywhere between 3-6 months. 

In the pantry In the fridge 
Oyster sauce (unopened)Best-by + 3-6 months for best quality 
Oyster sauce (opened)3-6 months for best quality

How to store oyster sauce?

Keep it sealed 

The lid or cap of the oyster sauce jar or bottle is its defense against contaminants. Therefore, It is very important to make sure the lid is tightly sealed on the jar when the sauce is not in use. 

This is an important storage practice to lock the freshness of the oyster sauce and prevent spoilage due to microbes. 

Besides, wipe clean the area around the cap or lid to prevent the sauce from drying over there. The dried flakes fall it not eh sauce and deteriorate its quality.

Keep it away from heat 

When storing the sauce in the pantry or in the kitchen cabinet, make sure It stays away from heat sources like direct sunlight or stovetop. 

Similarly when storing it in the fridge, do not keep the bottle in the fridge door because this area suffers the most temperature fluctuations which deteriorate the quality of the sauce over time.

Cool and dark storage area

The rule of thumb for storing oyster sauce is to keep it somewhere dark, dry, and cool. A pantry or a kitchen cabinet will do fine.

Keep it in the fridge 

An opened container of oyster sauce must always be kept in the fridge. The low temperatures slow down microbial growth and help extend the shelf life of the sauce.

Can you freeze oyster sauce?

Oyster sauce does not freeze well due to its high sodium content. This is due to the Freezing Point Depression that results when any type of particles are dissolved in a solvent. 

The same applies to sweetened condensed milk which does not freeze solid because of the high level of dissolved sugar. Since the oyster sauce is a fermented product just like soy sauce, its ethanol content keeps it from freezing well. 


In this article, we answered the question “What happens if you eat expired oyster sauce?”, and how to tell If the oyster sauce is bad?





Hello, I'm Sana Ameer. I'm a student of Food Science and Technology at UVAS. I like to bake and I aspire to become a Food blogger.