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What Does Bad Bread Smell Like? The #1 Best Answer

What does bad bread smell like? Have you ever wondered what makes a bread smell bad? Most of the time, we sense a bad smell coming from bread even though it looks fresh and without having any mold.

When it comes to talking about bad bread, there are many signs that you can look for, which indicate that it is going into its rotten stage.

Bread, like every other food, has an expiry date, and once that date is crossed, it starts to release the individual chemicals contained in the bread, which spreads really quickly. 

Now you might be asking yourself how you could determine if bread is going bad by the smell. In this article, we will be talking about in detail about what bad bread truly smells like and how you can easily recognize it. 

What does bad bread smell like? 

Bad bread usually smells like vinegar infused with yeast and alcohol. If you have noticed that your kitchen where the bread is placed is starting to have an unpleasant odor, it is typically from fermented yeast in the bread.

What does bad bread smell like? 
What does bad bread smell like? 

Why does bad bread start to smell sour? 

The reason why bad bread starts to smell bad is that it has been overly fermented, meaning that high levels of alcohol and carbon dioxide have been emitted. 

If you or someone you know has bread lying around the kitchen countertop for a prolonged time, you will start to pick up this unfamiliar odor from the bread.

The reason why the bread smells like sour is that sometimes, they use too much yeast during the process of making bread.

The addition of too much yeast can cause the bread to go bad quickly and hence release a chemical smell that resembles sour.

That is why if you are baking bread and want to avoid this strong odor, then try leaving the bread to rise for a short time so as to not cause an over fermentation process.

Another popular cause of the sour smell of baked bread is the temperature.

As you all may be aware, the fermentation process requires heat, and as the surrounding temperature increases, the rate of fermentation increases, which means more alcohol and carbon dioxide are produced. 

That is why you should try to maintain a cool environment by lowering the surroundings Fahrenheit temperature when letting your dough rise.

Too Much Yeast During the Process of Making Bread
Too Much Yeast During the Process of Making Bread

Why does my bread smell like unfamiliar chemicals? 

When it comes to bread, many people have also complained and argued that their bread smells like chemicals, and there are several reasons for it.

One of the major reasons why bread smells like chemical is because of the bleached flour that is used. 

Many companies out there make use of flour that has been previously bleached or refined to a state with other chemicals.

This addition of flour with other ingredients such as yeast could cause chemical reactions to take place during the fermentation stage and release these smells.

It is important to keep in mind that for bread to remain fresh, all the ingredients used need to be balanced out perfectly, as one mistake could cause the bread to start getting moldy and release smells. 

Another major cause of chemical smell appearing from bread is due to over-proofing.

Now you may be asking yourself, what is the proofing stage? Well, to put it simply, proofing is the final stage of resting that a bread undergoes after it has been shaped into a loaf and before placing it in the oven. 

If you leave your bread out for too long to proof, you may run the risk of having a bread flat and dense. As I have mentioned earlier, in the fermentation process, yeast converts sugar into alcohol and carbon dioxide. 

Carbon dioxide is the main chemical responsible for the dough to rise, and so if the bread is left to overproof, the bread will lose all its carbon dioxide during baking which is released into the atmosphere, creating an unpleasant and unhealthy air quality.

The thing about these chemicals is that they may cause other foods to start going bad, like other bread lying around in the kitchen.

Proofing is the Final Stage of Resting the Bread
Proofing is the Final Stage of Resting the Bread

How and when does bread start to go bad? 

One of the major reasons that cause bread to go bad is the moist and humid environment.

Bread, like many other food products, cannot tolerate warm and moist temperatures for too long.

For this reason, it is necessary that you always keep your bread in a normal room temperature environment to prevent it from going bad quickly.

Typically speaking, the bread usually lasts for three to four days in a warm environment before it starts to release its odor, but if it is placed in a cool place, it can last up to a week and even longer.

If you want to keep bread for a long time, then you could consider storing it in the fridge, as bread lasts for more than six months when kept in refrigerators.

You may remember that we mentioned earlier that bread starts to smell bad before you can see any noticeable physical mold on it. However, sometimes bread can also smell bad due to internal mold within the bread. 

Preservatives such as sorbic acid, potassium sorbate, sodium benzoate, etc, release anti-mold acids that prevent the molding of bread, thus minimizing the risk of bread smelling bad

Furthermore, if you are someone who is allergic to gluten, you may notice that your gluten-free bread starts going bad really quickly but have you wondered why this happens frequently? 

The reason behind this is that gluten-free bread contains fewer preservatives which fight off mold; hence these bread release odor more than bread that contain preservatives and gluten.

Breads Lasts for Long time when Kept in Refrigerators
Bread Lasts for a Long Time when Kept in Refrigerators

What is happening when bread smells bad?

During the stage when the bread only smells bad and there are no molds on it, it is at this stage when spores are beginning to grow and spread through different parts of the bread.

The fungus in the bread starts to germinate and spread, absorbing all the nutrients and moisture along the way.

Although it may not be noticeable at first, this stage is quick, and within no time, you will start to notice that the intensity of odor increases.

When the fungus is spreading, it seeps deeper into bread and creates its “home,” which continues to absorb nutrients and moisture. 

If you are starting to physically see moldy bread, it is best that you discard the entire loaf instead of cutting portions off where mold was found.

The reason why you should do this is because the smell released by the mold may be trapped within the bread parts where there is no mold. 

Once this molded bread is ingested, it can not only cause sickness but also an upset stomach. The harmful chemicals that cause the unpleasant odors in the bread may disturb your digestion and cause vomiting. 

That is why whenever you notice a bad smell coming from bread, you should instantly wrap it in a sealed plastic container or bag and throw it away. 

Moldy Bread
Moldy Bread