Which of the following best defines cross contamination?

• A. The transfer of harmful bacteria from one food to another.
• B. Bacteria growing due to overheating.
• C. Bacteria killed by cleaning.
• D. Food contamination due to packaging.

Answer: (A)

Cross contamination is about the transfer of harmful bacteria from one item to another. It happens when bacteria move from raw foods, dirty surfaces, or contaminated hands and utensils to ready-to-eat foods, often through shared cutting boards, knives, or storage containers. This definition fits best because it focuses on the movement of microbes between foods rather than growth or killing of bacteria.

The other scenarios describe different issues: overheating can cause bacteria to grow if foods are kept at unsafe temperatures, but it’s not about transferring bacteria between foods. Cleaning or sanitizing can remove or kill bacteria, so that’s the opposite of cross contamination. Packaging-related contamination is about contamination entering food from packaging itself, not the transfer that occurs during handling and contact between foods.