Certified Professional Food Safety (CP-FS) Practice Exam

Which type of foods have a pH less than 6 and are most likely to react with metals like copper?

1. Sweet foods

2. Salty snacks

3. Acidic foods

4. Fatty foods

The correct answer is: Acidic foods

Acidic foods are those that have a pH level below 6, which means they contain a higher concentration of hydrogen ions. This characteristic causes these foods to have a tart or sour taste, common in items like citrus fruits, vinegar, and certain fermented products. The interaction between acidic foods and metals, especially copper, occurs because the acids can lead to chemical reactions that may leach metal ions from the cookware or storage containers. This is notably a concern when using copper utensils or cookware with acidic substances, as it can result in the corrosion of the metal and potential contamination of the food. In contrast, sweet foods tend to have a higher pH and do not exhibit the same reactivity with metals. Salty snacks generally have varying pH levels but are not classified as acidic in the same way. Fatty foods also do not possess the acidic properties that would lead to reactions with metals. This makes acidic foods the most relevant category when considering pH levels and metal reactions.