During sampling, foods should not be kept in which condition?

• A. Room temperature
• B. Spoiled
• C. Unlabeled
• D. Frozen

Answer: (D)

The main idea is to keep the sample as close to its original condition as possible so the test results reflect reality at collection. Freezing a food sample can cause physical and chemical changes—ice crystals can damage tissue, some nutrients or enzymes can be released or deactivated, and moisture can separate—altering how the sample behaves in analysis. That means the test results may no longer represent the sample’s true state when it was collected, which undermines the purpose of sampling. For many analyses, samples are kept cold but not frozen to slow changes without introducing the artifacts freezing can cause.

Room temperature can allow rapid changes or growth, spoiling indicates the sample is already compromised, and unlabeled means there’s no way to identify or trace the sample, all of which would invalidate the sampling process. But freezing is the condition that most commonly changes the sample in a way that can mislead results, so it’s not used during sampling.