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Does corn syrup go bad? Useful tips included

Does corn syrup go bad? Useful tips included

If you have just found an old bottle of corn syrup on your pantry shelf and wonder if corn syrup goes bad, you are in the right place. Here you will learn that and several other helpful tips about light corn syrup and dark corn syrup.

Just this past weekend we were rearranging our pantry and I am amazed at what I found. What made it really impressive is that we have only been in this new house for six months.

So if I have this many containers of various syrups and oatmeal after six months, I hate to see it in two years. 

I vow here and now to keep an organized pantry.


Ok, I vow to try real hard.

Now on to learning about corn syrup.

The short answer is if corn syrup is stored properly it will not go bad. Your bottle of corn syrup has an indefinite shelf life and can last an indefinite period of time. 

If you notice the “Best By” date has passed that doesn’t mean that you should eat the syrup. It just means that you will get the best results using it by that date.

Now, if the corn syrup was not properly stored it may go bad. If your syrup is cloudy, it should be thrown out. This cloudy appearance of hazy appearance means the growth of mold has likely begun to grow. 

Also, if your corn syrup is bubbly it has likely turned and you should discard it.

How to tell if corn syrup has gone bad

The best way to tell if corn syrup has gone bad is to smell it and look at it. If it is cloudy or hazy it has gone bad. 

If your syrup looks yellow the best way to know if it has gone bad is to give it the smell test.
If the corn syrup smells sour or off, it has gone bad. You will know a bad odor if you smell it. Trust your instincts and your nose. 

Light corn syrup can develop a yellowish tint over time but that doesn’t necessarily mean that it has gone bad. 

If this happens to your jar of corn syrup, know that it is likely to do time and not spoilage.

How to store corn syrup

The best way to store corn syrup is in its original container, sealed in a cool dry place such as your pantry. You can store corn syrup in the refrigerator if you prefer.

However, if you do store the syrup in the fridge keep in mind that it will thicken up and be difficult to pour when you are ready to use it. 

If storing the syrup in the fridge, consider setting it out about 30 minutes before you plan to use it. That way, it can warm up and it will be easier to pour.

How long does corn syrup last

Corn syrup can last indefinitely. The trick to keeping corn syrup for a long time is to tightly seal the lid after each use. Then store it out of direct sunlight and heat. 

You can keep it in the fridge but make sure that it is tightly sealed first because moisture can cause the syrup to crystalize.

For the absolute

Dark corn syrup vs light corn syrup

Light corn syrup does not mean light on calories. In this case, light is actually referring to the color of the syrup and the flavor.

Light corn syrup has a milder sweet flavor than dark corn syrup. Dark corn syrup has a rich nutty flavor and is dark in color.

When thinking of light corn syrup vs dark corn syrup consider that the light one has a hint of vanilla and the dark has a caramel flavor.

You may see or hear people reference light corn syrup as white corn syrup. This is because it is clear corn syrup and has no color. The terms white corn syrup and light corn syrup mean the same thing. 

You may see or hear people reference dark corn syrup as brown corn syrup. They are the same thing. It is simply that the name has changed over the years. 

Dark corn syrup doesn’t have vanilla in it. Instead, it has can sugar and that is where the caramel flavor or flavor of molasses derives from.

Can I eat expired corn syrup

Yes, you can eat expired corn syrup if it passes the visual inspection and the smell test. The expiration date is simply a “Best By” date. This just means you will have the best possible results when using the syrup before that date. So if you have an unopened container of the stuff, don’t just toss it. 

You only need to throw it out if it is bubbly, cloudy or smells sour.

Can you substitute dark corn syrup for light?

Yes, in most recipes you can substitute dark corn syrup for light corn syrup. You can also generally substitute light corn syrup for dark corn syrup.

Now, there are a few differences between light corn syrup and dark that you should keep in mind. The biggest is that light corn syrup has vanilla in it and the dark doesn’t. 

For example, when baking a pecan pie ask yourself if you would prefer a bit more of a molasses or nutty flavor in the pie. If that is the case, then use light corn syrup.

On the other hand, if you would prefer a hint of vanilla or a light sweetness to the pie then choose light corn syrup.

Also, the best corn syrup for pecan pie is the one that you already have in your pantry. 

In all honesty, when you are reading recipes that call for corn syrup you are reading the personal preference of the recipe creator. Since the two corn syrups interchange so well, I recommend following your own palette and adding your unique twist to the recipe.

Personally, I most often prefer dark corn syrup because I love the nuttiness of it.

Can corn syrup get moldy?

Yes, corn syrup can get moldy. If the container was not sealed properly or if the lid was left off for too long mold can grow. It is rare for corn syrup to get moldy but if water gets in it, it can surely happen. 

If the corn syrup is bubbly or has a foamy top, it is likely moldy. If you notice either of these, I would throw out the syrup and replace it with a brand new bottle. 

Note: If you see either of these, don’t do a taste test. I know that it is tempting but skip it.

Summary notes:

• Corn syrup can generally be used past the expiration date on the container. 
• To a large extent the shelf life of corn syrup really depends on how it is stored.
• Discard corn syrup that is cloudy, smells foul or is foamy. Toss it if it has an alcohol-like smell. 
• Dark corn syrup can be substituted for light corn syrup in recipes. 
• Light corn syrup has a milder taste than dark corn syrup.
• Light corn syrup contains vanilla.
• Dark corn syrup does not contain vanilla.
• Dark corn syrup has a nutty taste or a taste of molasses.
• You can store corn syrup in the fridge but it will be difficult to pour.
• Store corn syrup in a cool dry place and out of sunlight. A dark pantry is the best storage space for a kitchen cabinet.

Several years ago Karo syrup started making corn syrup, both varieties, without high-fructose corn syrup. Their brand is also gluten-free. 

If you are purchasing a different brand for corn syrup, I recommend that you read the ingredients prior to purchasing. Each manufacturer creates its recipe differently.

But don’t confuse high fructose corn syrup with the corn syrup you see on the grocery shelf. They are indeed different things. 

A fun fact about baking cookies with corn syrup instead of sugar is that your cookies will turn out more chewy than crunchy. Read all about how to use corn syrups when baking. They have some interesting uses of corn syrup that are worth learning. 

As I learned, corn syrup is essentially liquid sugar, known as invert sugar. This means that it is liquid at room temperature.

So next time I make cookies, I will make a batch with corn syrup and let you know the difference. 

Cooking is fun!