Snack time is usually uneventful, which is why this incident caught my full attention.

My son had just opened a sealed bag of sour cream–flavored chips when something strange fell out along with the chips—a small, firm blue disk that clearly didn’t belong there. Instantly, my thoughts raced through every possible worry. I told him to stop eating right away and took a closer look at the object. Unsure of what it was or how it ended up in the bag, I took a photo and posted it online, hoping someone could help solve the mystery.

The response was almost immediate.

People from all kinds of backgrounds—some saying they worked in food manufacturing or quality assurance—began sharing their insights. After reading their explanations and doing a bit of research myself, the answer became clear. The blue disk wasn’t a foreign contaminant or a child’s toy. It was actually a test piece used during food production to verify that safety and metal-detection systems are working properly before products are approved for sale.