ketchup bottle
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Plenty of scientists spend lots of time working on projects that will never directly affect our lives. For instance, you’ll never be traveling to Mars. I don’t care what sort of down payment you gave that guy in Belize; no spaceships are leaving anytime soon. So even though it sounds far less exciting, we should never overlook the efforts of scientists who set out to make our day-to-day lives better: People like the University of Melbourne’s Dr. Anthony Stickland whose studies include figuring out the best way to get ketchup out of a bottle.


“If you tilt a bottle of water, the water flows out because it is a liquid. But tomato sauce prefers to be in the bottle because it is technically a solid, not a liquid,” Stickland explains, expounding on ketchup (which the Aussies sometimes call “tomato sauce”) for his university’s website Pursuit. Accepting that ketchup has a unique makeup is at the forefront of the Chemical and Biomolecular Engineering expert’s condiment pouring advice. The burger topper is actually composed from tomato solids suspended in liquid and those solids create a continuous network, providing additional strength and resisting motion. In fact, if we want to get very technical about it (and Pursuit does), ketchup doesn’t even obey Isaac Newton’s Law of viscosity, making it what is called a “non-Newtonian fluid.” Yeah, you never knew that ketchup had some PhD-level properties going on!

However, a field of physics called “rheology” specifically deals with these kinds of unique solid/fluid hybrids. “Suspension rheology explains all the phenomena seen in tomato sauce bottles and provides the answers to the perennial sauce question, which can be tackled in three main steps,” Stickland states. Finally, you lost us all at non-Newtonian fluid Stickland, just give us the steps…

First, shake the bottle with the lid on to mix all that ketchup back together evenly. Second, turn the bottle upside down and let the ketchup settle into the neck. Third, tilt and pour, adding a touch of force by smacking the bottle if the ketchup won’t come out.

It’s that simple! And if it doesn’t work, just go to the old standby… Step four: Curse loudly and start again from step one.