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๐Ÿค” Does Cornstarch Go Bad? Here’s The BEST FAQ For Answers! ๐Ÿค”

🤔 Does Cornstarch Go Bad? Here’s The BEST FAQ For Answers! 🤔

So you have the urge to bake, but the recipe calls for cornstarch. You remember the bag of corn starch buried in the back of the pantry, and on digging it out, the thought, does cornstarch go bad pops into your head. This article provides you with the answer!
Cornstarch, more commonly known as corn flour, maize flour/starch, or maizena is a by-product when corn is being processed for various products.

It is a carbohydrate that is extracted from dry corn kernels. 

It is white and is available in powdered form.

The primary use of cornstarch is to thicken soups, sauces, glazes, pies, casseroles, etc. 

More about this later.
All food goes bad eventually. 

Generally, air and moisture are the main culprits. 

Not to mention those pesky germs that are present in everything.
But seriously, cornstarch will spoil when exposed to moisture. 

This allows for the growth of mold. 

Not really what you want to eat.
Now, check out these fun facts about cornstarch:
Thomas Kingsford invented the process of making cornstarch, and it is said that Colgate and Company were the first US producers of cornstarch back in 1844.
Until 1851, cornstarch became popular among individuals for starching laundry and industrial applications.
Moreover, it has increased its uses to include cosmetics, cooking, and even science experiments! 

Pretty neat!
One of today’s well-liked uses of cornstarch is for bath bombs

It does a good job at holding all of the ingredients together right before you toss the bath bomb into the tub!

Here is a fun fact for the kids on a rainy day—a mix of 1 part of water with at least 1.5 to 2 parts of cornstarch is a well-known classroom experiment, shear-thickening fluid. 

Also—did you know that cornstarch is used as an anti-stick agent on medical products made from natural latex and medical gloves.

It can be used to manufacture bioplastics.

In general, cornstarch doesn’t go bad

However, it can go bad if it’s incorrectly stored or contaminated. 

While cornstarch never spoils, it’s also worth noting that the ingredient surprisingly doesn’t lose its potency unlike its baking colleague, baking powder.

How long does cornstarch last?

Well, it has an indefinite shelf life

Now that is a bonus.
Yes, we did say it goes bad. 

But in and of itself, corn starch does not go off. 

It needs an outside source such as moisture or humidity.
Corn starch has a very low, almost no water content. 

Therefore, it has little chance of bacterial or mold growth. 

Unless it comes into contact with a source of water, which includes humidity or condensation.
To prevent your corn starch from going bad the next step would be learning how to store it.

How to store cornstarch?

The best way to store corn starch is in an airtight container in a cool dry place.

Keeping it in the original packaging or placing the cornstarch in a sealable plastic bag and then placing it in an airtight container, will achieve the best results.

This prevents moisture from getting in and also keeps it fresh. 

It must also be kept away from extreme heat.

How long does cornstarch last after opening?

Since cornstarch has an indefinite shelf life in a sealed package. 

Once opened, it needs to be stored in a dry place such as a pantry. 

It can last a very long time as long as it does not come into contact with any moisture, it will last indefinitely.

Can I store cornstarch in the fridge?

Fridges have a moisture content and could spoil your cornstarch. 

Any foods are at risk of condensation from the changing temperatures of the cold refrigerator or freezer to room temperature. 

Even a few minutes at room temperature can cause condensation to settle on your cornstarch, which should stay perfectly dry. 

The climate-controlled pantry or cupboard is the best place to keep cornstarch.

How to tell if cornstarch has gone bad?

Cornstarch is a white powder, so any discoloration of the powder is a sign that something is not okay.

Any sign of black dots or yellowing of the powder or any colors that you may see is a sign that it needs to be ditched.
Here are five signs that your cornstarch has gone bad.

The appearance of bugs

The presence of bugs is the first sign that your cornstarch is already bad.

If you see those bugs, usually black or brown in color, better to trash the cornstarch.

The presence of mold

When moisture comes into contact with cornstarch and it gets left in an unsealed container, mold will form. 

This is very dangerous and must not be consumed at all.

Your cornstarch has a bad smell

A strong odor is a sign the cornstarch is off, also a sour smell means it is time for the trash can.

A sour taste is a warning

If you have not seen any bugs or mold and you have not detected a strong odor that does not mean the cornstarch is okay. 

Check the taste if you are not sure how long it has been stored. 

Cornstarch has little to no smell. If it tastes or smells sour, then whatever sauce you add it to will taste sour as well. 

Time to throw it out.

When you find lumpy cornstarch

This means moisture has got into it. 

At this point it could still be usable, just check there is no mold or it tastes sour.

Can you use expired cornstarch?

Corn starch does not usually have an expiry date, it has a use-by date. 

As long as it has been stored properly and does not come into contact with moisture, it will be good to use. 

However, this is really up to you to decide. 

If it is a recent use-by date, it should be good to go. 

Checking on the above signs or for any discoloration should give you an idea if it is good to use. 

If it has been more than a year and open and not in a container, I would ditch it.

Another interesting point here would be how long can you keep food made with cornstarch; any food can be kept as long as the quickest expiring ingredient.

Ways to use cornstarch

Most of us know that cornstarch is used in cooking. 

But there are many uses in the home for corn starch.
Let’s have a look at how cornstarch can be used at home for things other than cooking:

  • Can be made into a homemade glue or clay for play dough
  • Mix water, sugar, vinegar, and cornstarch to make paper mache paste
  • Can be used as a deodorizer in fridges. To remove or prevent smells in fridges, mix equal parts (I use 1 tablespoon of each) of cornstarch and baking soda in a small glass dish and place in the fridge. Change after a week.
  • Add a drop of essential oil to this and use it as an air freshener in the home. It will absorb odors floating around the house.
  • Stop shoes from smelling by just sprinkling cornstarch into your shoes. 
  • Stain remover. Simply sprinkle cornstarch over the stain and leave it for a couple of minutes.
  • Polish silverware. Mix water and cornstarch in a bowl. Rub the mixture using a damp cloth onto silverware.

As we said, cornstarch is used as a thickening agent in soups like Vegetable Soup, sauces such as Cheese Sauce and Stir Fry Sauce, gravies, and stews such as Chicken Stew and Old-Fashioned Beef Stew.
I also use cornstarch when I roll out fondant, it prevents the fondant from sticking to the surface. 

It can then be dusted off. 

Also prevents your hands from getting sticky. 

This tip was given to me by my cake decorating instructor.
Cornstarch added in place of part of your normal flour also makes a lighter mix for scones, so they rise more. 

A tip that was given to me by another baking friend.
Beating a teaspoon of cornstarch in with your cream makes it a stiffer whip and stabilizes whipped cream when stored in the fridge.
Here is another fun fact: Cornstarch doesn’t react well with acidic ingredients. 

Tapioca starch or arrowroot will work better for thickening acidic mixtures. (I have learned something new here)
Cornstarch imparts a glossy, translucent sheen to the mixtures it thickens, so it tends to be used more in sweets rather than savory sauces. 

To prevent lumps, stir the starch into a small amount of cool water, then stir this starch slurry into the hot liquid you want to thicken.
As you can see, there are many uses for cornstarch in and around the home. 

And you thought it was just another pantry staple, but it is so much more with many helpful uses.
The good news about cornstarch is that it has a long shelf life if stored correctly.

The bottom line

With all that cornstarch can do, it should not be sitting on the shelf in your home for any length of time.

It can be used in myriad ways around the house and in cooking and baking.

It is fairly cheap to buy and it makes normal flour go a long way while improving the taste and texture of baked goods.

Cornstarch would be a more environmentally friendly household product as it is a natural product. 

So using it in place of canned air fresheners would be a natural alternative.

Pure cornstarch is gluten-free, so it can safely be used for those that have a gluten intolerance.

I hope that you have enjoyed reading my article on cornstarch and that you have learned a little something new in the process. 

I sure have learned a lot more about cornstarch than I knew before. 

This really is a most versatile product and well worth keeping on hand in your pantry.

How To Store Cornstarch 🤔

How To Store Cornstarch 🤔

Suppose you are wondering how to store cornstarch. Read on to learn the best way to keep the ingredient fresh!


  • Cornstarch
  • Sealable plastic bag
  • Airtight container


  1. Place the cornstarch in a sealable plastic bag.
  2. Put the sealed cornstarch in an airtight container. 
  3. Keep it in a cool and dry place like your cupboard.

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