Can molasses go bad?

In this brief article, we will answer the question: can molasses go bad and the different ways of identifying bad molasses. In addition, we will discuss the health consequences of eating spoiled molasses and how to store them properly to avoid their spoilage.

Can molasses go bad?

Yes, molasses can go bad over time. Mold or fungal attack can occur, causing it to develop a bad smell and altered taste. 

You should be very careful and never eat spoiled molasses, especially if they are contaminated with molds as they can produce harmful mycotoxins that can make you very sick (1-2)!

Molasses is a viscous product derived from the refining of sugarcane or sugar beets into sugar, and its sugar content may vary depending on factors such as the age of the sugarcane plant, extraction method, and raw materials used.

Proper storage and handling practices are essential for prolonging the shelf life of molasses. While the labels on molasses jars often indicate a lifespan of 2 years, it can be stored for a few to several years depending on how it is stored. 

It is important to note that “best by” dates on molasses jars do not necessarily mean the product has gone bad in terms of safety but rather may indicate a decline in flavor and freshness. Nevertheless, you should always check your molasses for signs of spoilage.

How to identify bad-spoiled molasses?

To identify bad or spoiled molasses, you can look for several signs such as:

  1. Mold growth: Unlike honey, molasses can develop mold. Look for spots of mold on the surface of the molasses or around the container.
  1. Unpleasant taste: Spoiled molasses will have an unpleasant taste. If you regularly consume molasses, you can easily identify a change in flavor when it spoils.
  1. Off odor: Expired molasses may have an off odor. One way to identify this is by comparing the smell of a new bottle of molasses with an old one.
  1. Thick and grainy texture: If the molasses has gone bad, you may notice that its consistency is thicker and more viscous due to crystallization or a grainy structure.
  1. Darkened color: Spoiled molasses may have a darker color than fresh molasses.

It’s important to note that using spoiled molasses in your recipes can negatively impact the taste of the end product and potentially make you sick (1-3). Thus, if you observe any of the above signs in your molasses, it is recommended to discard the entire container and purchase a new one.

Can expired molasses make you sick?

Yes, expired molasses can make you sick and lead to different foodborne illnesses (1-3). Past the expiration date molasses can have spots of bacteria and molds growing on it that are hard to spot. If you consume such molasses, then it may lead to an upset stomach or even food poisoning (1-5).

Molds on molasses can produce mycotoxins that cause gastrointestinal issues such as nausea, vomiting, abdominal pain, and diarrhea. It may also trigger allergic reactions like itching, redness, swelling, or hives (1-2, 4). 

While bacterial contamination with pathogens like Salmonella and Clostridium botulinum can cause salmonellosis and  botulism, resulting in symptoms like diarrhea, fever, abdominal cramps, vomiting, blurred vision, muscle weakness, difficulty swallowing and speaking, and even paralysis in severe cases (3, 5). 

So, it is very important that you discard any spoiled molasses and avoid further consumption to ensure  your safety.

What is the shelf life of different types of  molasses?

The shelf life of different types of molasses (i.e., light, dark, blackstrap, sulfured and unsulfured Molasses) can vary depending on storage conditions and whether the bottle is opened or unopened. 

If the molasses comes in an unopened bottle with an expiration date, it is generally safe to consume within two years from the manufacturing date.

However, if the molasses has been stored properly, it can still be consumed even for a longer time, as the date is a commercial estimate and may not accurately reflect the product’s actual shelf life.

Once a bottle of blackstrap molasses has been opened, it is recommended to use the product within one year to ensure optimal quality. Proper storage in the refrigerator before and after opening can help slow down the deterioration process and extend its shelf life.

It’s important to note that while the expiration date provides a general guideline, the key factor in determining the safety and quality of the molasses is its appearance and smell. If the molasses looks or smells spoiled, it is not safe to use.

The shelf life of your molasses may also vary depending on the specific brand of molasses and the storage conditions. So, it is very important to always inspect your molasses and follow proper storage rules.

How to store molasses to prolong their shelf life?

To store molasses and prolong its shelf life, you can follow the next tips:

  1. Choose the right storage container: Store molasses in an airtight container or keep it in its original glass bottle with proper packaging. This helps prevent air exposure and maintain its quality.
  1. Store in a cool and dark place: Keep the container in a cool, dry, and dark area, such as a kitchen pantry, away from direct sunlight and heat sources like stoves. This helps prevent the molasses from spoiling or deteriorating.
  1. Avoid moisture: Ensure that the container is tightly sealed or covered with a lid to prevent moisture from entering. Excess moisture can compromise the quality of the molasses and promote bacterial growth.
  1. Refrigeration (optional): While it’s not necessary, molasses can be stored in the refrigerator, especially in hot temperatures, to maintain its freshness. 

However, refrigeration may cause the molasses to become more viscous and sticky. If refrigerated, gently heat the molasses before using to reduce its viscosity.

  1. Avoid freezing: Freezing molasses is not recommended as the high sugar content prevents it from freezing properly. Instead, freezing can lead to crystallization and a thicker consistency, potentially compromising the quality of the molasses upon thawing.
  1. Transfer tips: When transferring molasses to another container or jar, you can spray the opening of the receiving container with cooking spray. This will make the transfer less messy and easier to clean.

By following these storage tips, you can help prolong the shelf life of molasses and maintain its quality over an extended period.


In this brief article, we answered the question: can molasses go bad and the different ways of identifying bad molasses. In addition, we discussed the health consequences of eating spoiled molasses and how to store them properly to avoid their spoilage.


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2. El-Said AHM. Mycotoxins and Invertase Enzyme of the Mycoflora of Molasses in Upper Egypt. Mycobiology [Internet]. 2002 [cited 2023 Jun 3];30(3):170. Available from:  

3. Nakano H, Yoshikuni Y, Hashimoto H, Sakaguchi G. Detection of Clostridium botulinum in natural sweetening. Int J Food Microbiol [Internet]. 1992 Jun 1 [cited 2023 Jun 3];16(2):117–21. Available from:  

4. Dantigny P, Conika M, Fontana A, Schorr-Galindo S. Mycotoxins during Consumer Food Storage. Mycotoxins Food Beverages Innov Adv Part I [Internet]. 2021 Jun 10 [cited 2023 May 31];51–68. Available from:élique-fontana-sabine-schorr-galindo   

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