A university professor has revealed the best way of getting tomato sauce out of a glass bottle isn't by banging on the end.
Dr Alan Mackie, a professor of Colloid Chemistry at the University of Leeds, England said that banging on the end of a glass bottle will make the sauce inside too runny which is why it will inevitably spurt out all over your meal.
Instead, he says tapping on the neck of the bottle will give you much better control over the flow.
Dr Mackie explained that tomato sauce is made up of thin tomato and water particles, and thicker long chains called polymers. When you turn the bottle upside down, these polymers become entangled and the sauce becomes thicker, which is why it doesn't flow out of the bottle.
When you bang on the end of a bottle however, these polymers untangle and the sauce thins - resulting in a very quick and uncontrolled flow.
Dr Mackie explained: "What's happening in the bottle is that there's a polymer in there, a thickener.
"When you turn it upside down, the polymers entangle and it doesn't flow. When you hit it on the bottom, you tend to make the entire jar liquid if you hit it hard, which is not what you want and that's why it comes out in a big splurt."
It's why tomato sauce tends to spurt everywhere when you use this method.
However, Dr Mackie said if you tap on the neck of the bottle, only the sauce at the top will become more liquid and you can control the flow more easily.
The professor and British chef, Matt Tebbutt put the theory to the test by using the two methods to fill pots of tomato sauce.
He managed to fill the pots neatly and quickly by just tapping on the neck, while Matt's tomato sauce went everywhere when he banged on the end.
Dr Mackie said: "What I would do is tap the neck region and that liquefies the neck region and has a controlled flow over your chips."
Watch the video here