Which of the following is NOT a sign of food contamination?

Hives are a physiological reaction often linked to allergies and can occur in response to certain foods, but they are not a direct sign of food contamination. Food contamination primarily involves the presence of harmful microorganisms, chemicals, or foreign objects in food, which can manifest through visible signs such as color changes, unusual odors, or microbial growth.

Color changes and unusual odors are classic indicators that food may be spoiled or contaminated. For example, a change in color might indicate that meat is no longer fresh, while an off-putting odor can suggest bacterial growth or spoilage. Microbial growth is a clear indicator of food contamination, as this indicates the presence of pathogenic organisms that can lead to foodborne illness. Hives, on the other hand, while serious in the context of dietary reactions, do not reflect the condition or safety of the food itself but rather an individual health response.