We all have our talents. I will confess that one of my own few (maybe only) gifts is the ability to get ketchup out of a bottle when others have struggled to do so to no avail. I’ve sat across the table from fry-eating friends as they’ve shaken, tapped, struggled, sighed and sneaked delicate peeks inside to see if progress had been made, and, finally, in frustration, they’ve reached for their knives to try to move things along. At that point, if not before, I offer help, taking hold of the glass bottle and giving a confident tap just below where the neck of the bottle expands into the wider part. Voila! Ketchup. That’s the sweet spot, people. I am telling you, it works every time.
Yet science now says there’s a better way. Anthony Stickland, a senior lecturer in Chemical and Biomedical Engineering at the University of Melbourne’s School of Engineering who has researched solid-liquid separation and suspension rheology (an area of physics that contends with the deformation and flow of matter), has suggested that his field of study provides the key to getting ketchup to flow perfectly from the bottle with nary a splat or sputter.
“Suspension rheology explains all the phenomena seen in [ketchup] bottles and provides the answers to the perennial sauce question, which can be tackled in three main steps,” Stickland recently said in a university release.
Stickland broke down these three scientifically proven steps to get ketchup flowing at just the right rate:
First, with the cap firmly on, shake the bottle to reunite any solids that have separation from the liquids in your ketchup and to remove any “plugs” in the neck of the bottle and avoid that gross watery stuff that can accumulate at the top.
Second, still keeping the cap on, turn the bottle so the neck is pointing down, shaking and whacking it to get the ketchup to the opening.
Third, remove the cap and tilt the bottle toward your intended target (burger, fries, hot dog or what have you). If you keep tilting and tilting until the bottle is, essentially, upside-down and the ketchup still doesn’t move, you need to offer “some sort of encouragement, like tapping, slapping or whacking,” Stickland said, but you don’t want to whap it so hard it splats out all at once.
“You need to find the ‘sweet spot’ of force needed to move it towards your burger,” Stickland advised. “Start by pointing the open end of the bottle toward your food at an angle of around 45 degrees 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.”
Personally, I’ll eschew science and stick with my method. I am telling you, once you find that spot on the body of the bottle, just below where it meets the neck, and give it one swift hit with the heel of your hand, you’ll be good to go.