Does Corn Syrup Go Bad?

If you’re wondering “does corn syrup go bad?”, you’re in the right place. Corn syrup is used as a sweetener, but only a handful of people use it on a regular basis. Most people use it only from time to time, or even less frequently. That’s why some people often find themselves in a situation where they have a bottle of corn syrup that’s been stored in the pantry for years and they’re not sure if the corn syrup will be fine or they should just discard it. If you’re in a similar situation, the first thing you should know is that corn syrup can go bad, but it happens very rarely and only if it has been poorly stored. If it was stored properly (and most people store corn syrup the right way), it should be fine. Let’s dive into some of the issues related to storing, shelf life and going bad of corn syrup.

How to store corn syrup

Corn syrup should be stored at room temperature or a little less. Storing it in the pantry is a default for many people, but you can store it in a cupboard in the kitchen as well. Storing in the fridge isn’t probably the best idea, because the syrup will become thicker. Make sure the area where you keep bottles with corn syrup is dry (that shouldn’t be an issues for anyone).

Lots of syrups
(credit:Keoni Cabral)

Once you open the bottle, make sure it’s tightly sealed when not in use. That’s critical because if it’s not sealed, some food particles or bacteria can find their way into the bottle and that (after some time) will result in spoilage of the syrup. If you’ll always remember to seal the bottle tightly before puting it back into the cupboard (or wherever you keep it), that won’t happen.

Shelf life of corn syrup

Each bottle of corn syrup should have a “best by” or “use by” date somewhere on it, but you should realize that, in case of corn syrup, that’s only a suggestion. You can keep it for a very long time (meaning years) and if it’s stored properly, it will be fine. You don’t have to believe me, just check out Karo syrup site, where they state that “Karo syrup is safe to eat for an indefinite period of time whether it has been opened or not opened.”. That means that the “best by” date is just a recommendation and that manufacturer guarantees that the quality of their product will be best for that period of time. The only thing to remember from this paragraph is this: if stored properly, corn syrup can be stored for years.

How to tell if corn syrup is bad

As I’ve mentioned earlier, in certain cases corn syrup can go bad. First thing you should know is that light corn syrup might turn yellowish with age, but that’s not harmful and that corn syrup definitely isn’t spoiled or bad.

If the corn syrup appears to be cloudy or hazy, that might be a sign of spoilage because some food particles or bacteria got inside. If there is film or bubbles on its surface, chances are it’s spoiled. General rules are: examine it visually and smell it. If it smells somewhat like alcohol or vinegar, it’s definitely spoiled. If it’s just a little cloudy or hazy, but it smells fine, taste it. After tasting it you’ll be sure if it’s spoiled or not. Please note that consuming only a tiny bit of it won’t cause any negative health-related consequences. Of course you should consume it as a part of the test only if you’re pretty sure that it’s fine. If it looks spoiled, just discard it.

As you should know by now, corn syrup can go bad, but it’s very unlikely to happen. Unless you’ll store it unsealed, it will be fine for years, so you don’t need to buy another bottle of corn syrup every time you only need a bit of it.