Maple Syrup’s Shelf Life: Can It Go Bad or Expire? How To Tell


Maple Syrup has become a staple in many homes, but this delicious sweet treat does come at quite a hefty price. Unfortunately, after leaving it unattended for a couple of weeks, you open it up just to find a thick layer of mold on the top!

But, does maple syrup go bad? You would be surprised to learn how little people know about this naturally sweet treat, especially how to store it!

Luckily today, we will have an in-depth look at how maple syrup goes bad, when, and how to prevent it the best you can. This way, you can ensure to always have the freshest syrup on hand and prevent throwing away money!

What Is Maple Syrup?

image of maple syrup can go bad

Maple syrup is a common type of natural syrup that can be found in large part of the world. It is especially common in colder areas like North America and Canada, where maple trees grow in abundance.

But unfortunately, it isn’t available around the globe, making it a completely foreign ingredient to many people. Shockingly enough, not even many locals know exactly what it is!

So, getting right to it, maple syrup is made from the sap of a maple tree. Many different types of maple trees can be used, including a syrup maple, red maple, or black maple tree.

While all of these will produce slightly different flavors in the syrup itself, they will all have the same storage methods and shelf life.

Different Quality Maple Syrups

You can also find different grades of maple syrup, which indicate the quality. And believe it or not, they will have varying shelf lives!

Grade A syrups have a few sub-categories, all of which include the highest quality of syrup you can find. The flavor is rich and pure, and the color is saturated. These include;

  • Golden colored with a delicate maple flavor
  • Amber-colored with a pure, rich taste
  • Dark brown color with a more robust flavor
  • Extremely dark brown or black color with an intensely strong maple flavor

Then, you will often find processing-grade maple syrup. These are lower in quality and often cheaper. They are still sold in stored but won’t have the same rich flavors and color as Grade A maple syrup does.

And finally, you find substandard grade syrup, which is the cheapest and often used to make other products. Substandard maple syrup also has the shortest shelf life, which is why they also contain a ton of preservatives.

Nutrition Of Maple Syrup

Maple syrup isn’t exceptionally high in vitamins and minerals. It only contains some calcium, potassium, iron, zinc, and manganese. But, it is high in antioxidants, containing roughly 24 different kinds.

This syrup, like most, is also very high in sugar. It contains roughly 2.12 ounces (60 grams) of sucrose (table sugar) per 1/3 cup.

So, use maple syrup in moderation to prevent any serious health side effects.

Does Maple Syrup Go Bad?

Unfortunately, maple syrup can go bad! While it isn’t an extremely perishable ingredient, it isn’t immune to going off. Luckily, it is far more likely that you will use it all before it goes off!

It is also important to note that when we say maple syrup goes bad, it more often than not only starts showing signs of mold growth on the surface. But, there are many ways to deal with this, which we will discuss a little bit later.

When maple syrup is unopened, it will last for at least 1 year inside the pantry. When opened, you should store your maple syrup inside of the fridge, where it will last for another year.

And, if stored in the freezer, it can last indefinitely! However, we would still recommend using it within a couple of months.

Why Does Maple Syrup Go Bad?

As with all things, the main cause of food going bad is bacteria. There are many different types, but all of them ultimately only need one of three elements to reproduce and thrive. (*)

Bacteria requires optimal environmental conditions, moisture, and food. For the environment, the pH should be relatively neutral – not too acidic and not too alkaline. Maple syrup is relatively neutral.

It should also have a temperature of between 40-140ºF (4.4-60ºC) to reproduce best. Anywhere cooler or warmer will either slow down reproduction completely or kill the bacteria.

Next, bacteria need moisture. Maple syrup despite having a very thick consistency does contain a lot of moisture which then feeds the bacteria.

And finally, because maple syrup contains loads of sugars, the bacteria have an unlimited amount of food.

Signs Maple Syrup Has Gone Bad

There is only really one sign of bad maple syrup. The others take a very long time before they start appearing. These signs include;

  • Mold growth on the surface
  • A slightly sour (acidic) flavor forming
  • Sour tart smell

Mold growth is the number one sign that your maple syrup has gone bad. The mold will first start forming in spots on the surface of your maple syrup.

The longer you leave it, the more mold will grow, eventually covering the entire surface area. You will see a thick layer of white film, which sometimes have shades of blue and green on it.

Only under extreme conditions will maple syrup change its flavor and its aroma. When these things happen, the maple syrup is beyond saving.

How To Save Moldy Maple Syrup

You can still use maple syrup even after mold starts appearing on the surface. But, you have to follow our in-depth guide to ensure you won’t get sick from any bacteria.

1. First, remove the layer of mold on the surface. You can use a spoon or fork to remove any moldy pieces carefully. If you want to, you can also strain the syrup through a fine-mesh sieve. Just ensure that none of the smaller moldy pieces pass through.

2. Boil the syrup for safety. Next, place the syrup inside a small saucepan and bring the mixture to a boil. Once boiling, reduce the heat and simmer the syrup for 5 minutes. This will ensure all leftover bacteria are killed.

3. Cool and bottle the syrup. After being boiled, allow the maple syrup to cool at room temperature. Then, place it back inside a sterilized glass container or bottle. You can have a look at this tutorial on how to properly sterilize glass jars for food.

How Do You Properly Store Maple Syrup?

Maple syrup is very shelf-stable and has a long shelf life. While it doesn’t easily grow mold, there are still better ways to store it.

Storing Maple Syrup At Room Temperature

You should only store unopened maple syrup at room temperature. When stored in glass, it can last up to 4 years. And, inside of plastic bottles, it will remain good for about 2 years.

That being said, it is best to use unopened maple syrup within a year. This will ensure it has the best flavor.

When storing maple syrup at room temperature, keep it away from direct sunlight and other heat sources. Increasing the temperature in any way can cause more rapid growth of bacteria.

Storing Maple Syrup In The Fridge

Once your maple syrup has been opened, you have to store it in the fridge. This will help extend its shelf life for another couple of years. 

Make sure your container is still airtight. Also, your fridge should have a stable working temperature below 40ºF (4.4ºC).

When storing maple syrup inside of the fridge, it won’t completely prevent bacteria from growing on the surface of the syrup. However, it will help slow down the growth to a great extent.

This ultimately makes the maple syrup almost invincible against bacterial growth.


Learn more: Our Ultimate Guide To The Best Maple Syrup Alternatives For Any Recipes


Hopefully, after reading our in-depth article on “Does maple syrup go bad?”, you can confidently say that it can, but it is highly unlikely. Due to its nature, maple syrup is extremely shelf-stable and is not likely to ever truly expire!

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