Ketchup is delicious, but also different to other liquids we are familiar with.
Newtonian fluids like water pour faster the more we tilt the container they are in this is because they have a linear relationship between force and acceleration.
Tomato ketchup however is a shear thinning nonNewtonian fluid which means its behaves like a thinner liquid when there is force applied, and can behave more like a solid where there is little to no force supplied.
Knowing this is super helpful when it comes to pouring ketchup from a glass bottle, so here are my quick tips:
1 Shake the bottle with the lid on
2 Remove lid and hold bottle at a 45° angle
3 Gently tap neck of the bottle, increasing in force until you get the flow rate you want.

Also please ignore the title in the video I'm not actually a Tomato Sauce Scientist

Full video on Seven Sharp at https://fb.watch/63OSo5BCh/