Does soy sauce go bad? (+ How to spot)
In this brief guide, we will address the question, “does soy sauce go bad” as well as other related questions pertaining to the subject at hand like how much time does soy sauce take to go bad or what are some of the storage practices needed to prolong the shelf life of soy sauce.
Does soy sauce go bad?
For the most part, no, soy sauce does not go bad. It simply loses its flavour over the course of time. Soy sauce contains a huge amount of sodium which does not allow any microbe to survive and multiply.
Soybean is the most produced and consumed oil seed crop worldwide. In 2013, 226 million metric tons were produced in over 70 countries. Organically produced soybean represents less than 0.1% of total world production (1).
Items like soy sauce are used in small amounts while cooking, therefore such questions are very common and people often wonder if it goes bad or not. Well, you have your answer now.
As a matter of fact, soy sauce often lasts longer than its expiry date, simply because of the high sodium content. Sodium is a natural preservative that does not allow the growth of microorganisms. However, there are salt-tolerating yeasts and molds which can grow in foods that contain high amounts of salt, including soy sauce (3).
It will also retain its freshness and flavor after the expiry date for a good period of time before it starts to lose its efficacy and flavor. Keep in mind that it is still safe to consume. The only change you’re going to experience is a darker color and stronger aroma due to the oxidation process. According to the USDA, with an exception of infant formula, if the date passes during home storage, a product should still be safe and wholesome if handled properly until the time spoilage is evident. Spoiled foods will develop an off odor, flavor or texture due to naturally occurring spoilage bacteria. If a food has developed such spoilage characteristics, it should not be eaten (2).
How long does soy sauce last?
Depending on the brand manufacturer and whether the bottle has been opened or not, soy sauce can last from 6 months to about 3 years (or even more in ideal storage practices).
According to the USDA, an unopened bottle of soy sauce can be safely stored for 3 years at room temperature and for one month in the refrigerator once opened. Refrigeration ensures that commercial sauces and condiments stay fresh for a longer period of time. Shelf-stable commercial soy sauce is safe when stored at room temperature after opening. Quality, not safety, is the reason the labels on these products suggest that they be refrigerated after opening (4).
Reading the label is always the first option that you should be referring to when dealing with food products. Having said this, there is no guarantee that the sauce is determined to go bad right after its expiration date as mentioned before.
An important factor to prolong the shelf life of soy sauce is storing it in the refrigerator. With proper sealing, even an opened bottle of soy sauce can last much longer than usual if stored appropriately.
In a study, soy sauce was stored for 90 days at room temperature and under cold storage. The results indicated that the changes of physicochemical properties of the stored product depended on the types of raw soy sauce, heat-treatment and storage conditions, where the temperature was a determinant factor. Losses of chemical compounds and aroma and flavor were lower under cold storage (5).
Shelf life of soy sauce. (How to increase it?)
To increase the shelf life of your soy sauce, the best way is to store it in a cool and dry place. Obviously, the best practice is not to open the sauce without the intention of using it. In this way, your soy sauce will last upto 3 years.
There is a possibility where you open the soy sauce and now you are wondering where you should store it? Well, there is no hard and fast rule as to where it should necessarily be stored. All you need to do is make sure it is sealed properly in a cool, dry place and it will retain its best flavor and texture for up to 6 months, depending on its composition and packaging material, as well as on other factors, such as handling of the product.
Do you have to refrigerate soy sauce?
Like already mentioned, soy sauce contains a huge amount of sodium that naturally prevents it from going bad. However, storing it in the refrigerator will definitely help in maintaining the optimal flavor and shelf life. In general, the shelf life of food can be extended after its sell-by date if it is refrigerated properly (7).
Just tightly seal the cap and put soy sauce in the fridge for the next time you want to use it. Storing it in the refrigerator is an ideal storage condition when optimal results are desired.
Other FAQs about Sauces which you may be interested in.
How long does spaghetti meat sauce last in the fridge
Does Worcestershire sauce go bad?
How to tell if soy sauce has gone bad?
Being a fermented beverage, it is highly unlikely that soy sauce will spoil in a traditional sense. It can only go bad if proper hygiene and safety measures are not ensured. However, it can spoil. Although soy sauce is fermented and pasteurized, some microorganisms, such as halophilic bacteria, are able to grow in the soy sauce (6).
Unlike other soy products such as milk that can make you seriously ill if consumed expired, soy sauce does not have similar results. This fermented product will not affect your health even after its expiry date, unless it is contaminated with molds, yeasts or bacteria that are salt-tolerant and grow in high-salt-containing food (3).
There are few exceptions to this case because fermentation does not guarantee neutralizing the outside contaminants. If your soy sauce was kept in the refrigerator without a lid, then there are chances that a mold or any other unfavorable particle can enter the sauce.
To check this, you can take out the soy sauce in an open container and do a visual and sensory analysis of the sauce. Microbial contamination leads to increase in turbidity of the sauce (5).
Look closely to see if there are any unwanted particles floating at the top. You can also take a whiff to identify strange odors. If so, then something has clearly caused your soy sauce to turn rancid. The flavor changes during the storage period, as well as the properties of the sauce (5).
After all that we have discussed, it is safe to say that soy sauce can go bad. I mean, any food item will go bad if you are not storing it properly. In the case of soy sauce, the chances are highly unlikely because there is no special method involved.
In this brief guide, we addressed the question, “does soy sauce go bad” as well as other related questions pertaining to the subject at hand like how much time does soy sauce take to go bad or what are some of the storage practices needed to prolong the shelf life of soy sauce.
- Hartman, Glen L., et al. Organically grown soybean production in the USA: Constraints and management of pathogens and insect pests. Agron, 2016, 6, 16.
- Food Product Dating. United States Department of Agriculture. 2019.
- Rawat, Seema. Food Spoilage: Microorganisms and their prevention. Asian j plant sci Res, 2015, 5, 47-56.
- Foodkeeper. Food Safety and Inspection Service. United States Department of Agriculture.
- Liang, Ru, et al. Characterizing the effect of packaging material and storage temperature on the flavor profiles and quality of soy sauce. J food sci technol, 2020, 57, 1544-1552.
- Sumague, Ma Josie V., et al. Predisposing factors contributing to spoilage of soy sauce by Bacillus circulans. Philipp J Sci, 2008, 137, 105-114.
- Sharif, Zainon Binti Mat, et al. A study on shelf Life prolonging process of chili soy sauce in Malaysian SMEs’(Small Medium Enterprise). IOP Conf Ser Mat Sci Eng, 2017, 203.