Cologne doesn’t need to be shaken as it’s made out of moving molecules. These molecules are only static if left below freezing temperature (32 degrees Fahrenheit or 0 degrees Celsius). Even if shaken, you still get unmixed cologne that is already inside the spray tube.
The problem with shaking the cologne is that it does nothing at best and it also arguably damages your perfume. Let’s see what the consensus on shaking perfume is.
Air has the potential to damage cologne in the long term. This means that shaking the cologne would create air bubbles that could potentially speed up the cologne maturation process, turn it darker, and eventually take its scent away. But does air truly get inside the cologne bottle?
Does are get into the bottle when spraying?
The presence of air bubbles in the perfume bottle doesn’t necessarily aid the scent. Shaking the bottle shows up various air bubbles, but these bubbles’ number doesn’t increase if you shake the cologne more.
Some people believe you can simply shake a bottle of cologne to create more bubbles which would help the fragrance oils mix better. But these fragrance oils are already mixing all the time as their molecules aren’t static. The molecules in the essential perfume oils are moving all the time.
This is why you aren’t doing anything when shaking perfume. A shook cologne bottle doesn’t get more intense.
The theory that unshook perfume doesn’t smell is demystified by the famous Titanic. Perfume oils were discovered here just a few years ago. Found in sealed bottled after they’ve been sitting at the bottom of the ocean for 89 years, these perfume oils still smelled good. They smelled potent as they filled an entire scientific laboratory room with their scent.
Why did these perfume oils have a smell if not shaken for 89 years? It’s because perfume doesn’t change when shaken and because the water didn’t get inside the bottle.
Cologne is already shaken during transportation
Even if shaking cologne would enhance its scent, you shouldn’t try to do it on purpose. Cologne is already shaken in its transportation boxes from the laboratory to the store, into storage, and then to your home.
Should you shake cologne?
Most perfume bottles are hermetically sealed. Air doesn’t get in them. Likely, perfume makers don’t extract air from the bottles as most are already filled nearly to the top of the bottle. It would only be possible to add air to a perfume bottle when you’d spray it only when the said perfume bottle is empty.
So should you shake cologne or not? Given air doesn’t get inside the bottle due to hermetic sealing and given essential oil molecules aren’t static, perfume should not be shaken.
Are there any benefits to shaking a perfume bottle? Not really. One of my favorite perfumers, Roja Dove, is presenting his creations without shaking the cologne. Is he wrong for doing so? Would there be any benefits to his long-studied fragrance notes being shaken? I highly doubt there are many reasons behind this trend.
At the same time, we must acknowledge around 20-30% of people who wear perfume shake the bottle. This is a simple survey result from all of the forums I’ve read on this topic and a surprising finding when I asked my friends about it as I was sure this would have been 0%.
Light and oxygen hurt perfume. Applying kinetic energy to these perfumes doesn’t improve the scent and it can harm it. Most fragrance oil compositions are already matured (oud is a possible exception) or macerated. You are doing nothing by shaking the bottles. This is why you should not give in to this shaking superstition.