How to Tell If Molasses is Bad

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By: Rachae's Nosheri


Molasses is a sweet syrup used to flavor gingerbread cookies, baked beans and barbecue sauce. For maximum freshness it should be stored in an area away from direct heat or sunlight and should remain cool and dark when stored in containers.

Unopened molasses has an indefinite shelf life once opened, though its quality may deteriorate over time. Therefore, it’s essential that consumers learn how to identify whether their molasses has gone bad before using it.

Sour Smell

Molasses is a thick liquid sweetener that doesn’t spoil as quickly as other liquid sweeteners such as maple syrup and honey; however, improper storage may still lead to spoilage. To maintain optimal freshness of molasses storage conditions in order to preserve its freshness and extend shelf life as long as possible (ideally, pantry), due to its hygroscopic nature which attracts moisture from the air and increases mold growth risks; once mold appears it should be discarded promptly.

Molasses doesn’t change in appearance when it goes bad; instead it develops an unpleasant flavor. If you’re uncertain if a jar is too old, taste it – if its flavor differs significantly from what is typical for you it could be past its prime and no longer suitable. Keep in mind there are numerous types of molasses so familiarity is key when tasting.

Molasses that has gone bad is easily identifiable if its smell becomes pungent and off-putting; fresh molasses has an attractive sweet aroma that quickly changes once spoilage occurs, becoming more pungent over time as its composition degrades – as well as developing a weird chemical aroma.

Lastly, any container of molasses contaminated with bacteria or pathogens must be discarded immediately as this poses a significant health risk as bacteria and pathogens could spread throughout its contents – and potentially make you unknowingly consume contaminated molasses.

Most bottles of molasses come with an expiration or best-by date printed on them, not necessarily meaning it has expired or will spoil by this point, but does indicate its quality may begin to degrade significantly after this point. With proper storage conditions, however, molasses may last well beyond its best-by date without becoming unusable – although if it does go bad it still should be safe for baking purposes but will lose both its sweetness and flavor.


Molasses can become unusable over time, yet it can be difficult to tell when that has happened. Over time, its flavor and sweetness may decline significantly making it less desirable in cooking and baking applications, and mold growth could result in food-borne illness. To check whether molasses is going bad it is best to inspect its color, scent and consistency of its bottle.

Molasses is hygroscopic, meaning it absorbs moisture and air from its surroundings, meaning the more moisture enters, the quicker it spoils. Therefore, it’s crucial that it’s stored in an ambient space without direct sunlight that could hasten degradation.

Store molasses in a dark and cool area such as your pantry or kitchen cabinet to extend its shelf life. However, freezing may also work; just be careful as doing so could alter its texture and flavor.

Signs that molasses is bad include its cloudy or murky appearance. This could indicate it has fermented, as the consistency may change to thicken or crystallize over time. When consumed, such food could potentially cause illness.

Though molasses has an extended shelf-life, it may still spoil when exposed to high temperatures. When this occurs, its flavor and texture may change drastically, as will its nutritional value – even becoming more acidic!

If your molasses has changed color, smells sour or appears cloudy, it may be time to dispose of it. While expired molasses can still be used in recipes, its flavor won’t compare to fresh. A simple test for whether or not your molasses has gone bad is to take a taste – if its flavor turns bitter or sour then chances are high it has likely gone off and should be discarded immediately.


If your molasses is turning brown, it may have become rancid due to natural chemical reactions that take place when left for too long in a bottle. Sugar begins decomposing into darker color compounds as its component parts decompose over time; moreover, as time passes the consistency will become thicker and thicker until eventually you must throw it away as soon as the change appears in its hue. If this occurs to you then throw out immediately!

When storing molasses, it is crucial that it is stored in a cool environment in order to prevent its premature spoilage. Furthermore, tightly sealing containers will help ensure air does not enter and cause it to spoil as quickly.

One sure sign that your molasses has gone bad is the presence of mold spores, caused by its hygroscopic nature and ability to draw in water and other contaminants. Mold spores may form on its surface or within its container itself; should this happen, discard immediately!

Unother telltale sign that your molasses has gone bad would be any change in flavor. Over time, even with proper storage practices in place, its flavor can naturally deteriorate; though still safe to eat, its taste will have diminished significantly from when first opened.

While storing molasses, be sure to wipe its lip with a clean paper towel so as to prevent moisture entering and spoiling it prematurely. Furthermore, make sure it is stored in a cool, dry area as heat and sunlight may also contribute to its spoilage.

Date printed on molasses labels can often serve as an accurate gauge of freshness; however, this may not always reflect when its shelf-life ends; many brands provide a “best-by” or “best-if-used-by” date which doesn’t correspond with an expiration date but rather provides guidance as to when its optimal quality has been reached.


Molasses contains both water and sugar, making it harder for bacteria to grow; however, over time this still may happen; once spoilage occurs it will usually have an unpleasant or even foul odor which is the first indication it has gone off-track.

When opening a jar of molasses that smells foul, it is time to dispose of it immediately. Even though your jar may not yet have gone bad yet, that doesn’t guarantee that it won’t at some point soon – the best way to tell is either through sniffing or tasting the contents; sweet-tasting molasses should have no unpleasant odor; any time that its sweet aroma has changed to an offensive or foul aroma, then that is an indicator that its days may have come and gone forever – throw out!

Proper storage of molasses is critical to prolong its shelf life and keep it tasting its best. Unopened jars should last up to one year in cool and dark locations; once opened however, store it in the refrigerator as heat and humidity can quickly cause it to spoil faster than anticipated.

Avoid opening and closing the jar too frequently as this introduces air and moisture that may contribute to mold growth. Wipe down its lip after each use to prevent bacteria from colonizing it and potentially growing on it.

Keep in mind that the date printed on a jar doesn’t correspond with its expiration. Instead, manufacturers provide best-by or best-if-used-by dates, which indicate when products will still be at peak quality for consumption – though that might change over time.

Although molasses is relatively straightforward to identify when it goes bad, there may be more subtle indications. To stay on the safe side and extend its freshness for as long as possible, read carefully the label and follow storage instructions provided by each brand – especially older sugarcane-derived varieties which need extra TLC when it comes to preservation. By following these tips you can ensure your molasses is always at its peak condition!

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Rachae's Nosheri

Rachael’s Nosheri is a Jewish deli located in 120 S. 19th St, Philadelphia, PA 19103. We serve breakfast and lunch comfort foods and deli sandwiches. Our extensive menu and reasonable prices make us a popular destination for locals and visitors alike. Our food is pretty good if you’re in the mood for deli sandwiches, and we’re known for our American, Bagels, Breakfast, Lunch Specials, and Sandwiches.

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