Humans have enjoyed commercially produced ketchup since the mid-19th century, but many have been struggling to get it out of the bottle ever since.
Now, science may have discovered a better way to get to the bottom of that bottle. Australian researcher Anthony Stickland, who teaches chemical and biomolecular engineering at the University of Melbourne in Australia, says there is a proper way to coax ketchup from its container.
Stickland says the reason the condiment is so hard to pour is because “it is technically a solid, and not a liquid.”
As Stickland explained to Melbourne's Pursuit, ketchup is actually a “soft solid” like paint or toothpaste, which means it doesn’t yield to pressure the way that milk or water does.
“With tomato sauce, it’s got all of the solid particles of the pulp of the tomato sticking it all together,” Stickland says in an accompanying YouTube video. “And so those solid particles create a network that has a strength to it, and you need to apply enough force to overcome the strength of that network to make the sauce flow.”
“It’s all about applying the force to the sauce to push it out,” he added.
Stickland recommends a three-step process for pouring ketchup the proper way.
First, “start by giving the sauce a good shake” to spread the solid particles evenly throughout the remaining ketchup in the bottle, Stickland says. “Remember to keep the lid on, of course.”
Next, turn the bottle upside down and thrust it downward — then swiftly stop. This should pool the remaining ketchup near the neck and top of the bottle. “If there’s not much left in the bottle, you may need a strong whack to dislodge tomato sauce from the bottom."
Finally, the professor says to carefully turn the bottle upright so that the ketchup stays near the neck. Remove the cap, then slowly tilt the bottle downward at a 45-degree angle “with one hand around the bottle neck, and the other delivering gentle but firm taps on the bottom of the bottle.
“Increase the force of the taps until you balance the force applied with the mechanical strength of the sauce in order to get it to flow,” he adds.
Sound like too much work?
If all else fails, Stickland tells the New York Times that “sticking a knife in will stir it locally,” and usually allow the ketchup near the opening to flow, “which may be enough.”