Did your culinary urges seize you some time back and make you go on a shopping spree? Did you buy several things that you thought you would need for cooking? But the craze faded out soon, and the things you purchased were out of sight and out of memory!
Now you have found that long-forgotten carton of soy milk and are trying to figure out what to do with it. You may be baffled by questions.
Is it still good enough to be used? Does soy milk go bad? How to use it optimally?
The best thing is that soy milk has lean protein and possesses several health benefits. You can use it as a substitute for cow’s milk in vegan and vegetarian cooking because it has fewer hormones and cholesterol.
It’s smooth and delicious, so you can even create your preferred drinks with it!
The bad news is that temperature changes can have an impact on it. Mold can grow in it. That is why it has to be sealed or refrigerated to retain its quality.
Do you know that there are many varieties of this milk? The two main types are:
- shelf-stable
- refrigerated
There is also a gluten-free variety for those who have gluten sensitivity.
Let us see how you can know whether the soy milk is spoiled, how to store it so that it retains its quality for a longer time, and how long it can last.
How To Know If Soy Milk Has Gone Bad

It is easy to find out if your soy milk is spoiled:
- Smell it: If it emits a weird smell, maybe it is spoiled. The smell is due to the growth of bacteria and mold. Usually, if you do not keep an unopened carton of the refrigerated variety of soy milk in the fridge for one night, it may give out a sour odor.
- Observe the texture: If it is thick and not runny, has curds or lumps, and is not off-white, then you should discard it.
- See the package: If it is bloated, it is an indication that the milk is not fit for use. The carton becomes bloated because of the gases released by the bacteria.
Make it a habit to pour the soy milk into a glass before drinking it.
Wondering why?
The reasons for this are:
- When you drink it from the bottle or carton, the bacteria present in your mouth may enter the package, and the milk may go bad more quickly.
- You can note its texture. If it is thick, lumpy, or curdled, discard it and avoid consuming rotten stuff.
How To Store Soy Milk

You can store soy milk just like you store other milk substitutes such as oat milk, almond milk, or coconut milk. The right way of storing your soy milk will depend on the type of milk.
If you bought a carton of soy milk from a shelf in the grocery store, it is a shelf-stable variety. You can keep this type of soy milk in a cool and dry place, for example, in your pantry. If you like, you can keep it in your refrigerator, but it will not make much difference.
But when you buy a refrigerated package of soy milk, you have to keep it in the refrigerator.
When you open either the refrigerated or shelf-stable type of soy milk, you have to keep it in your fridge. If you keep it in a warm place, there is a risk of shortening its longevity.
Now: When you keep it in the fridge, do not keep it near the door. It will ensure that it does not experience too many temperature fluctuations.
If you have prepared soy milk at home, you must keep it in the refrigerator at all times.
How about freezing your soy milk?
You can freeze it if you want to store it for a long time. But it is not recommended.
Take an ice tray and pour the milk into it. Place the tray in the freezer. Let the cubes of soy milk freeze. Then take out the tray and put the cubes in one airtight container or freezer bag. Put the container or freezer bags inside the freezer.
This way, your soy milk will retain its quality for about two months.
Here is the deal: After you thaw the soy milk, its taste and texture may change to a certain extent. Why not use the thawed milk for cooking purposes so that the change is not noticeable!
Remember: It is better to use the fridge instead of the countertop to thaw it.
How Long Soy Milk Lasts

You will find a Best Before date on its carton or bottle. It might be between 8-12 months after production. If you use it by that time, you can enjoy the best quality milk.
However, soy milk may continue to be edible beyond this date. The approximate shelf life for each variety:
- A shelf-stable opened package of soy milk is edible for 7 to 10 days.
- Unopened, shelf-stable soy milk will be usable for 2 to 4 months after the Best Before date.
- Refrigerated, opened soy milk lasts for 3 to 7 days.
- Unopened, refrigerated soy milk is usable for 3 to 5 days after Best Before date.
- Homemade, refrigerated soy milk does not have preservatives, so it lasts for 3 to 5 days.
The Bottom Line On Soy Milk
You can safely store your shelf-stable soy milk package at room temperature if you have not opened it. If you leave an opened carton at ordinary room temperature, it may deteriorate faster. But the fridge is the best place for opened packages and the refrigerated variety of soy milk.