The method is straightforward: fill a small cup with water and place it in the freezer until it freezes solid. Then, place a coin on top of the ice and return the cup to the freezer.

Mark Coleman, a refrigeration expert in the UK, explains, "If the coin remains on the surface, your freezer has maintained a consistent temperature. However, if a power outage occurs, causing the ice to melt and refreeze, the coin will sink. This indicates that your food may have thawed and refrozen, increasing the risk of foodborne illness."

A submerged coin (right) indicates a power outage and potentially unsafe food. Photo: Idealhome

A submerged coin (right) indicates a power outage and potentially unsafe food. Photo: Idealhome

Coleman recommends placing the cup of water in the center or near the front of the freezer for easy observation. Avoid placing it against the walls or near vents, as fluctuating cold air currents can cause uneven freezing and thawing.

This simple trick offers peace of mind after being away from home or if you suspect a power outage. A floating coin signifies safe food, while a sunken coin warns of potential food poisoning and spoilage.

Good Day Sacramento called this trick "the cheapest way to protect your family's health and safety." For many, it's a reassuring measure in uncertain situations.

Bao Nhien (via Idealhome)