How Do I Know If My Molasses Has Gone Bad?

Tom Gaffey
by Tom Gaffey
Credit: Shutterstock / Halil ibrahim mescioglu

Molasses is a staple in many kitchens, and it’s a cornerstone of baking and southern cooking alike. Made of refined sugar from sugarcane, or even beet juice, this flavorful dark syrupy ingredient can add rich and unique flavor to any dish you fold it into. You can add it to anything from baked beans to gingerbread cookies, making it a versatile ingredient. But unlike honey, molasses does not last forever. Therefore you must know how to recognize when your molasses has gone bad.

Molasses can last about 18 months when properly stored by wiping the rim, sealing it tight, and storing it in a cool dry place. Signs that your molasses has gone bad include crystallization or separation of the substance. Other signs include visible mold, or a bad smell and taste. When your molasses is beyond its expiration date, dispose of it and buy a new jar.

Molasses is an amazing ingredient to have on hand throughout the year. It comes in handy when you barbeque in the summer, and also when you make holiday cookies in the winter. But this syrupy concoction has a shelf life. If you are wondering if your jar has gone bad, keep reading to learn all the signs that your molasses has gone bad.

How Long Does Molasses Last Once It’s Opened?

If you are reading this article then you probably have a few questions about how long molasses lasts, or if and when it goes bad. Unfortunately, molasses does not last forever. It also does not last for many years. Instead, the average lifespan of molasses once it is opened is between six and 18 months.

On average, you can expect your jar of molasses to last a year or slightly longer. Molasses is derived from sugar, so it will eventually begin to turn, and is also susceptible to mold, especially if it isn’t stored properly. Several factors can impact how long a jar of molasses will last once opened.

Three Factors That Impact How Long Molasses Will Last

  • How Well It Is Sealed: If you don’t wipe your jar of molasses down, or don't seal it tightly, then it will go bad faster. When air gets into your jar, molasses will turn faster and is more susceptible to mold.
  • Where It Is Stored: The storage location you choose will also greatly impact how long a jar of molasses lasts. If you keep it in the freezer or a hot environment (any temperature extreme) its lifespan will sharply decline. If you keep them in a cool dry place where you store your spices, it should last longer.
  • The Brand Of Molasses You Use: Not all molasses is made the same. It can be made from different products and can include different preservatives. If you want molasses that will last a long time, look at expiration dates when you are at the grocery store.

Five Signs That Your Molasses Has Gone Bad

1. The Molasses Has Separated

One way you can tell if your molasses has gone bad is if it appears to have separated. This can happen if the molasses is very old, or if moisture has gotten into the jar. Either way, molasses should always have a consistent color and viscosity. If you notice two different shades and textures, then toss your molasses and buy a new one.

2. There Is Noticeable Crystallization

Molasses can also crystalize over time. If you notice crystals in your jar, this is the sugar crystallization. This happens more often when the molasses is exposed to extreme temperatures (like storing it in the freezer).

Make sure you take a close look at the molasses in your jar before adding it to a recipe. Sometimes these crystals are not obvious until you scoop out a tablespoon of the product. If you notice these crystals, it is best to buy a new jar.

3. The Molasses Smells Or Tastes Bad

One of the easiest and most effective ways to tell if your molasses has gone bad is a simple smell and taste test. Because molasses is so dark and thick, it can be difficult to notice mold or other impurities. You can, however, easily tell if the molasses tastes bad or smells “off.”

If the molasses stinks or smells rancid, it has gone bad. If it tastes sour, funky, or somehow “off” it is best to dispose of the product and buy a new jar.

4. The Expiration Date Has Come And Gone

Another sign that your molasses has gone bad has less to do with what the syrup looks like and instead relies on the label. Molasses is not a forever-lasting nectar. It has a recommended shelf life. This lifespan will be reflected in its expiration date on the label.

Check the expiration date before using your molasses. This is particularly important if you reach for yours and can’t remember the last time you used molasses in a recipe. If the expiration date has long since come and gone, it is time to toss it and buy a new jar.

5. There Is Mold Growing On It

Lastly, one clear red flag that your molasses has gone bad is when you notice mold growing inside the jar. Mold can take several different forms in molasses. Most commonly it forms a white fuzzy layer around the sides of the jar or a thin layer of fuzzy clear or white film over the molasses.

Either way, take your time to inspect inside the jar for signs of mold. If you notice mold, then make sure you do not cook with this molasses. Doing so can cause a bad stomach ache. Instead, get rid of it and buy a new jar.

How To Help Your Molasses Last Longer

Always Use A Clean Spoon

If you are using molasses for baking, it can be tempting to use the closest measuring spoon you can find to dip into the jar. Resist this urge. Only use freshly cleaned and sanitized spoons when scooping out molasses. This will prevent any bacteria from forming inside the jar.

Wipe The Rim Before Sealing

Molasses is a very thick and syrupy substance. It can easily drip along the rim and outside of the jar. Use a hot damp and very clean cloth or paper towel to wipe the rim of the jar. Not only will this prevent the lid from sticking, but it will help you form a safe seal, and prevent bacteria from multiplying.

Seal The Jar Tight

Take time to make sure your jar of molasses is sealed tight. Don’t be lazy and seal it haphazardly. A poorly closed jar of molasses is likely to spoil much faster than a properly sealed jar.

Store It In A Cool And Dry Place

Where you choose to store your molasses is also very important. Resist the urge to store your molasses in the refrigerator or freezer. Find a kitchen cabinet or cabinet alternative that is cool and out of direct sunlight. Instead, keep it stored between 50 and 70 degrees, in a slightly cooler than room temperature, dark location.

Don’t Freeze Your Molasses

It might be tempting to put your molasses in the refrigerator or freezer like you do with your maple syrup. After all, this is usually a great way to help preserve foods for longer. However, freezing your molasses can cause the sugars in the jar to crystalize, which will render the product unusable, especially for baking. Instead, store it in a cool dark place near room temperature or slightly lower.

Summing Up How To Tell If Your Molasses Has Gone Bad

Molasses is a great ingredient to have on hand. It is a concentrated and unique flavor, and best of all it can be stored outside the refrigerator. While this ingredient is shelf-stable, it does not last forever. You should replace your molasses once it expires, which is usually around once every 12-18 months. If your molasses is separated, crystalized, or moldy, dispose of it immediately. If it smells or tastes bad, you should get rid of it and buy a new jar.

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Tom Gaffey
Tom Gaffey

Tom Gaffey is an expert writer who currently resides in Washington D.C. Tom has a passion for real estate and home improvement writing, as well as travel and lifestyle writing. He lived the last twelve years in Hawaii where he worked closely with luxury resorts and event planners, mastering his knowledge of aesthetics and luxury products. This is where he found his passion for home improvement and a keen interest in DIY projects. Currently, Tom resides in Washington D.C, and also working on his debut fiction novel.

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