Why would homemade soup fizz and smell?

Homemade soup fizzing and smelling can be a sign of a few things, none of them particularly good. Here's a breakdown of the likely culprits:

1. Bacterial Growth:

* The Smell: A sour, putrid, or even rotten smell is a clear sign of bacteria.

* The Fizz: This is less common but possible. Bacteria can produce gases that cause fizzing.

* The Cause: Leaving soup at room temperature for too long allows bacteria to multiply. This is especially true if it was not properly cooled and stored after cooking.

2. Yeast Contamination:

* The Smell: A yeasty or slightly alcoholic smell.

* The Fizz: Yeast produces carbon dioxide as it ferments, which can cause bubbles and fizzing.

* The Cause: Yeast is a common contaminant, especially in flour-based soups or those with ingredients like tomatoes or potatoes. It thrives in warm, moist environments.

3. Chemical Reaction:

* The Smell: A strong, pungent odor.

* The Fizz: This is less common but possible.

* The Cause: Some ingredients, like baking soda or vinegar, can interact and create gas when combined in specific ways. This can lead to fizzing and an unusual smell.

What to do:

* If you suspect bacterial growth: Discard the soup immediately. It's not safe to eat.

* If you suspect yeast contamination: It's best to discard the soup as well. However, if the smell is mild and you're desperate, you can try cooking it again at a high temperature to kill the yeast. This may not eliminate the taste, though.

* If you suspect a chemical reaction: Assess the situation and try to identify the culprit ingredient. You may be able to correct the issue or salvage the soup by removing the offending ingredient.

Prevention is Key:

* Cool soup quickly: After cooking, let it cool to room temperature before storing in the refrigerator.

* Store properly: Use airtight containers to prevent contamination.

* Refrigerate promptly: Don't leave soup out at room temperature for more than two hours.

* Beware of ingredients: Be aware of ingredients that are prone to contamination (like flour or tomatoes) and handle them carefully.

Remember, it's always better to be safe than sorry. When in doubt, discard the soup!