Why does my bread smell sour?

In this brief guide we will address the question, “Why does my bread smell sour?” as well as other questions pertaining to the subject at hand like how to tell if your bread has gone bad and what are the ways for short and long term storage of bread. 

Why does my bread smell sour? 

This problem arises either due to over fermentation or excessive yeast in bread. Bread is a fermented product that requires delicacy and balance in its ingredients. 

Bread having a sour smell is a common problem when it comes to homemade bread. Store bought bread rarely ever has a sour taste when it is fresh from the store. 

Your bread can also develop sourness when it has been kept longer than its expiration date. Now this is where it gets tricky! It is safe to consume after the expiration date, right? Yes. 

The expiration date is a rough estimate, but you also need to keep in mind that the enzymatic activity is still going and there is no absolute way to tell when exactly it will go bad. That is why manufacturers estimate a date and mention it on the label. You can still consume it as long as it doesn’t go stale.

This is exactly why freezing makes it easier for you to store your bread for longer durations because it stops the enzymatic activity. 

Can I eat bread that smells sour? 

Yes, it is safe to consume bread that smells sour. The sour smell of bread is usually there because of the processing method that is involved in its making. Taste is the detrimental factor when it comes to consuming such bread. If it tastes fine, it is safe to eat. 

How to reduce sourness in your bread? 

Like I just mentioned before, sourness is a result of over fermentation or adding to much yeast during the preparation of bread. 

The critical step is when you’re adding yeast in the water-sugar mixture. Proofing is the process in which you dissolve yeast in a fixed amount of water, based on how much bread you want to make. This is the step where you can get your ratios mixed up, resulting in a sour bread. 

Note: Do not add yeast in when the sugar-water mixture is boiling hot. Wait for it to cool down until lukewarm and then add yeast in the mixture. This will give you a proper texture and flavour.

For a detailed recipe on how to make the perfect homemade bread, you can click here

Sourness is a sign of spoilage of bread, there are other signs of spoilage as well. 

How to tell if your bread has gone bad? 

Like mentioned earlier, the best by date is just an estimate and your bread may still be fresh past this date. Therefore, as long as you are aware of the signs of spoilage, the bread will be safe to consume. Here are some classical indicators that help you identify that the bread is no longer fresh or safe to consume. 

  1. Mold

Mold is a type of fungus that grows in different colours. It could be black, green, white, or pink. If you see such a growth or color formation on your bread, you should discard it immediately. 

  1. Unpleasant odor 

This is perhaps the most common technique while handling any food product. Simply discard the loaf when you notice the odour of the bread has changed. It indicates either the presence of a contaminant or the growth of microorganisms. 

  1. Strange taste or hard texture

Even if your bread passes the first two indicators, and then does not taste right, it is better to just throw it away and not take any risks. Health is wealth! 

Similarly, if you leave your bread out in the open for too long, the bread will go stale and turn dry. This is also an indicator that your bread has now gone bad and it is time to throw it away. 

Other FAQs about Bread which you may be interested in.

Why does my bread smell like chemicals?

My bread smells like alcohol, can I eat it?

Why does my bread smell yeasty?

How to store bread so it doesn’t go bad?

Short term bread storage

If you wish to consume within a span of three weeks, you don’t have to do the extra work of wrapping it in a different plastic bag that it came in. Just wrap it up and put it in the freezer. The plastic bag will keep it fresh for about 3 weeks. After this period, your bread may start to develop a freezer burn. 

Long term bread storage

If you want to freeze your bread for a longer duration, you might want to put in some extra effort. Use a plastic wrap in this case to ensure the absence of unnecessary air. Once you have wrapped it with a plastic wrap, put another layer of aluminium foil or freezing paper. 

It is also a good idea to mention the date before you put it in the freezer. In this way, you will know when your bread is about to go bad. This method prolongs the shelf life of bread for upto 6 months depending on the freshness and quality of bread. If you freeze it any longer, your bread will develop the freezer burn. 


In this brief guide we have addressed the question, “Why does my bread smell sour?” as well as other questions pertaining to the subject at hand like how to tell if your bread has gone bad and what are the ways for short and long term storage of bread.