Quickest way to pour a liquid?

I am thinking honey, but my instinct tells me if should be the same answer, not matter what the viscosity.

If your are pouring honey from a long necked bottle, what is the fastest way to pour it? Just put the bottle upside down and have an interrupted stream while the bubbles go up the neck? Or tip it so there is a gap on top of the pouring liquid and you get a constant stream coming out?

Feel free to pepper the answer with explanations of all the physical phenomena involved.

Only IMHO but leaving a small gap between the liquid and the neck of the bottle, for air to flow through, has always given me the best results.

It makes sense that air would flow faster and you need less mass of air to fill the volume being emptied by the liquid, so you only need a small gap, say 5% of the neck, for air to flow through.

I’ve heard of a party trick that’ll let you drink a bottle of whatever faster than anyone else involving sticking a bendy-straw in the bottle for air intake first.
Can’t find a site with a cite right now, but it would correspond to the air theory.

Probably to use a vented container so that bubbles going up the neck don’t slow the flow. I’m thinking your standard lawn mower gas can.

to most rapidly empty a two liter bottle is to invert it and swirl slightly to set up a vortex. This lets air into the bottle and more rapidly empties it.

Try it. Don’t swirl too vigorously or it might take longer for the liquid to leave.

As for the honey…I’m pretty sure this is unswirlable…so my post is irrelevant


that raises another good questions for which my answer was just an assumption. Is the viscosity of the fluid an influencing factor in this?

Well, if you’re trying to empty the container and don’t care about refilling it, you could always “shotgun” it by inverting it and punching a hole in the bottom. I’ve done this with plastic containers of motor oil.

And cans of beer, freshman year in college. Woo-hoo!

Once the swirl is started you can speed things up by tilting the bottle away from vertical, just enough to limit the symmetry of the vortex, and reduce the size of the central air hole.

The basic physics here is that if the liquid pours out without an air path, the air above the liquid ends up with a low pressure, compared to the pressure outside the bottle. That higher pressure outside presses against the liquid, slowing the flow and eventually pushing bubbles into the bottle. If you give an air path, the pressures are equal and the liquid flow is not impaired.

If you don’t consider it cheating: For most viscous liquids like honey, you’ll also get a much faster pour if you heat it first, which lowers the viscosity. Hot honey should even be ‘swirlable.’

ETA: You could also greatly speed the evacuation of the vessel if you actually added pressure to the bottle. Instead of putting in a straw just to equalize the pressure above the liquid with the ambient pressure, put in a hose connected to an air pump.

well, the most practical application I had in mind was actually pouring honey out of a glass bottle, so that limits my options. A plastic straw would be the most likely option (disregarding the fact that I don’t have them at home).

So is it demonstrably true that the average blob and wait is less than the continuous trickle? While it is true that the air only needs very little room compared to the honey, the practical reality is that it is a bit hard to control that gap.

Best way to get your honey out?
“Honey, I want a divorce.”

Just make sure there are no guns in the house.

Specific to honey:

Heating honey to use it each time will prematurely cause crystals to form in the bottle. A plastic squeeze bottle will be faster than a glass jar, because you can pressurize behind the honey. A honey dripper will be faster for a glass jar of honey.


Well, here is the deal. I get my honey from locals who always sell it in glass bottles (reused from whatever liquor they drink, they call hangovers cost of sales). I have the squeeze honey bear (reused from some blah honey I once bought at the supermarket just to have the squeezer). The issue is getting said honey from the glass bottle into the squeezer (which is rather small and needs to be refilled often).

Set the bottle in a hot water filled pot. Let it sit for for 5 to 10 minutes. Pour it into the bear.

That last part sounded dirty and kinky, but I will give you the benefit of doubt.

Dunno about something flowy like honey, but a 11 gallon NASCAR gas can “can” be emptied in c. 6 seconds. Not sure how they do it tho-probably some sort of one-way valve on the bottom which opens only when the can is flipped upside down.

I don’t want to hijack the thread, but I’ve wondered this as well.