What is one key sign of food spoilage?

Mold or unusual odors are clear indicators that food has spoiled. When food begins to spoil, it can exhibit visible signs like mold growth, which is a type of fungus that thrives on decomposing organic matter. Additionally, the development of unusual or off-putting odors is often due to the breakdown of proteins and carbohydrates by microorganisms. These odors are a result of the byproducts released during the spoilage process, signaling that the food is no longer safe to consume.

In contrast, unchanged color, absence of odor, and firm texture do not necessarily indicate that food is safe or fresh. For example, some foods might retain their color even after spoilage, and lack of odor does not guarantee that spoilage hasn’t occurred. A firm texture might also be present in spoiled food, particularly if it is just beginning to spoil. Therefore, noticing mold or unusual odors is crucial for determining food safety, making it the key sign of food spoilage.