In kitchens and markets around the world, a simple technique has quietly been used for generations, often without us even realising it: tapping fruits.

Many of us have done it without thinking. Knocking on a watermelon to see if it’s ripe, flicking a mango to test its juiciness, or giving an avocado a gentle tap to check firmness. These small gestures are more scientific than they seem.

At first glance, it might feel like intuition or tradition, but tapping fruits is actually rooted in understanding acoustics. the same principles we use at RESONIKS to test the internal integrity of industrial components.

What Tapping Reveals

When you tap a fruit, you send sound waves through it. These vibrations travel through the fruit’s internal structure, its density, firmness, and moisture, and the sound that comes back tells you what’s inside. Ripe fruits give a deep, resonant sound. Underripe fruits sound tight or high-pitched. Overripe fruits sound dull or flat.

Our ears are performing a simple form of non-destructive testing, listening for internal consistency without cutting the fruit open. Studies have shown how sound patterns change with texture from watermelons and tomatoes to mandarin oranges proving that sound can accurately reflect what’s inside a fruit: Tomato and Orange Study

At RESONIKS, We Listen for Quality

At RESONIKS, we use the same principle, the science of sound, to ensure that industrial parts meet the highest quality standards. Instead of fruits, we “tap” metal components. Using Acoustic Resonance Testing, we listen to how each part responds to sound waves.

Every component has a unique acoustic signature, just like each fruit. If a part’s resonance deviates from its known healthy pattern, it signals a potential internal defect, such as a crack or void, even if it’s invisible to the naked eye. This allows us to perform non-destructive testing (NDT) at scale: fast, precise, and fully automated.

From Fruit Markets to Factory Floors

Whether it’s a melon or a metal part, the principle is the same: sound reveals structure. Where a shopper listens for the perfect “thunk” of a ripe watermelon, we at RESONIKS listen for the clear, consistent resonance of a flawless component.

By scaling up this simple human instinct “tapping and listening” we help manufacturers guarantee quality, reliability, and safety across industries like automotive, aerospace, and defence. By listening closely, whether to a piece of fruit or a precision engineered part, we reveal what the eye can’t see, ensuring quality from the inside out.