The Science Behind The Majesty Of Dancing Raisins

September 16, 2023 by Lewin Day 18 Comments

Have you ever thrown a handful of raisins into a tub of sparkling water? Or peanuts into beer? It seems like an altogether strange thing to do, but if you’ve tried it, you’ll have seen the way the raisins dance and tumble in the fluid. As it turns out, there’s some really interesting science at play when you dive into the mechanics of it all. [Saverio Spagnolie] did just that, and even went as far as publishing a paper on the topic.

The fundamental mechanism behind the dancing raisins is down to the bubbles in sparkling water. When dropped into the fluid, bubbles form on the raisins and attach to them, giving them additional buoyancy. They then float up, with some of the bubbles shedding or popping on the way, others doing so at the fluid surface. This then causes the raisins to lose buoyancy, rotate, flop around, and generally dance for our amusement.

[Saverio] didn’t just accept things at face value though, and started taking measurements. He used 3D-printed models to examine bubble formation and the forces involved. Along with other scientists, models were developed to explore bubble formation, shedding, and the dynamics of raisin movement. If you don’t have time to dive into the paper, [Saverio] does a great job of explaining it in a Twitter thread (Nitter) in an accessible fashion.

It’s a great example of cheap kitchen science that can teach you all kinds of incredible physics if you just care to look. Video after the break.

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Force Carbonating Root Beer With Dry Ice

July 27, 2012 by Mike Szczys 49 Comments

[Paul] is sick and tired of his homemade root beer being flat. He analyzed the problem with his carbonation techniques and ended up with a method of force carbonating beverages using dry ice.

He starts of by discussing the various methods that are used to carbonate beverages. There’s the old yeast and sugar trick that takes place inside of a sealed bottle. But this takes time, and if you don’t calculate the mixture correctly you could have over or under carbonated bottles (or exploding bottles in the case of glass beer bottling). [Paul] himself has tried the dry ice in a cooler full of root beer method. The problem is that the cooler isn’t pressurized so the carbonation level is very low. You need to have cold temperatures, high pressure, and the presence of carbon dioxide all at the same time in order to achieve high levels of carbonation.

His solution is to use a 60 PSI safety valve. He drilled a hole in a plastic bottle cap to receive the valve. He then drops a few chunks of dry ice in and seals it up. The valve will automatically release the gas as the pressure builds past the 60 PSI mark. What he ends up with is a highly carbonated beverage in a matter of minutes.

If you don’t mind spending some cash you can use an adjustable pressure regulator. This way you can carbonate just about anything.

[Thanks Steven]

DIY Fizzy Fruit

February 17, 2011 by Mike Nathan 37 Comments

co2inator

[Rich] over at Evil Mad Scientist Labs took it upon himself to make eating fruit a little more enjoyable for his kids by infusing it with CO2 using his CO2inator. Observing the same principles used in making soft drinks and force-carbed beer, he decided to build a CO2 pressure chamber for use in his kitchen. He gathered a handful of easy to find components to construct his rig, including a household water filter housing and a CO2 cylinder from a paintball gun. He has some helpful hints for those who are not familiar with the process, noting that refrigerated fruit absorbs the gas more quickly than warm, and that considering the water content of the fruit is important when selecting what to carbonate.

Once [Rich] had everything safely connected and checked for leaks, in went the fruit. After about half an hour to an hour, the fruit was carbonated, much to the delight of his children. This looks like a quick and fun project for adults and kids alike, that can easily fit into a busy weekend schedule.

[via Neatorama]