Rock Tumbler Doubles As Ice Cream Maker

When working with limited space or even with limited funding, finding a tool that can do many things for less space or cost than its separate counterparts is a tempting option. The most common downside is that these tools often can’t perform as well as the single-purpose tools they replace, with the obvious example being a pocket-sized multitool or Swiss Army knife. Even things like combination drill and driver tools, adjustable crescent wrenches, or even a kitchen stand mixer can’t quite perform as well as their dedicated counterparts. So when we find a tool that can do two things equally well, like this rock tumbler that can also make a delicious bowl of ice cream, it’s definitely noteworthy.

The project comes to us by way of [North_Stordeur] whose main goal was to create a delicious bowl of ice cream but was deterred by the cost of purpose-built ice cream makers. Making ice cream isn’t a particularly complex process, though, and [North_Stordeur ] realized that grinding down ice for ice cream shares similarities with tumbling and polishing rocks. Normally, the rocks to be polished are placed in a drum with grit and a liquid, then the drum is placed on the tumbler and spun, which causes the rocks to bounce around inside the drum with the grit and smooth out relatively quickly. Replacing sugar for grit, ice for rocks, and milk for the liquid, the ice eventually is worn all the way down, creating an excellent bowl of ice cream.

Truly, the only downside we could see with a build like this is that the drum in the National Geographic rock tumbler that [North_Stordeur] chose for this project looks like it would only make a single serving at a time. However, with picky eaters around who like their own additions to ice cream, this might be a perk as everyone can make exactly the style they like with their own choice of flavors. It’s an excellent discovery for anyone already grinding and polishing rocks or someone who has already built a DIY ball mill for any number of other uses.

Warmer Ice Cream?

What if you could tweak the recipe on ice cream to keep it frozen at higher temperatures? The idea comes from massive conglomerate Unilever. Among other things, the brand owns a wide variety of ice cream brands, from Ben & Jerry’s to the Magnum and Cornetto lines. Instead of running freezers at the industry standard of -18 °C (0°F), the company is experimenting with upping the temperature to -12 °C (10 °F) instead.

First off, you’d save a lot of electricity. Thanks to the way the industry works, the company actually owns the vast majority of the three million or so display freezers that are used to sell its stock to customers. Running at a higher temperature could slash the freezer’s energy use by 20% to 30%, according to the company’s calculations. The company also estimates that the energy used by these freezers makes up around 10% of its total greenhouse gas footprint, so it’s better for the environment too.

Of course, there’s savvy commercial reasons behind the idea. Unilever had noticed its ice cream sales dropping in 2022. The company believes this was in part due to retailers unplugging their freezers earlier than usual as winter approached, due to high energy bills. If the company’s freezers aren’t humming, they’re doing less business. If shaving down the freezer’s energy use helps retailers keep them plugged in and the lights on, that’s a net bonus to the company’s bottom line. It could also make their freezers unhospitable places for rival products, giving them an edge in the marketplace.

But this is all business intrigue. Let’s instead take a deeper look at ice cream.

Continue reading “Warmer Ice Cream?”

Sad clown holding melted ice cream cone

Freezing Out Ice Cream Machine Competition

We always knew that McDonald’s soft serve (you can’t really call it ice cream) machines are known to be finicky. There’s even a website that tracks where the machines are broken and, apparently, it is usually about 10% or more of them at any given time. But when we saw a news article about a judge issuing a restraining order, we knew there must be more to the story. Turns out, these $18,000 soft serve machines are in the heart of something we are very interested in: when do you own your own technology?

Cold Tech

There are apparently 13,000 or so of these machines and they are supposedly high-tech marvels, able to produce soft serve and milkshakes at the same time. However, they are also high maintenance. Cleaning the machine every two weeks (try not to think about that) involves a complete teardown. Worse, if anything breaks, you need a factory-authorized service person.

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An Automated Ice Cream Topper For The Ultimate In Zero Effort Desserts

It’s a highly personal facet of the eating experience, the choice of topping applied to your frozen dessert. Everybody has their own preferences when it comes to whipped cream, sprinkles, and chocolate syrup. Should the maintenance of those preferences become a chore, there is a machine for that, and it comes courtesy of [Kristen Vilcans] and [Ramita Pinsuwannakub] in the form of their Cornell University project as students of [Bruce Land]. Their Automated Ice Cream Topper holds profiles for each registered user, and dispenses whipped cream, chocolate sauce, and candy sprinkles onto ice cream at the simple push of a button.

The hardware seems simple enough until you appreciate the many iterations used to ensure that it works smoothly. The bowl of ice cream sits on a motorised turntable, and a can of whipped cream is suspended above it upon rails made from kebab skewers. A servo and lever operates the can to release the cream.  Meanwhile the sprinkles come from an inverted spice jar with a motorised disc to momentary align a hole with the jar’s spout, and the chocolate syrup comes courtesy of an air pump and some plastic tubing. The whole is controlled from a PIC32 microcontroller.

It is refreshing to see that such projects do not have to tackle especially high-tech problems to be extremely successful. We could all dispense our own toppings, but now we know there’s s machine for the task, who wouldn’t want to give it a try!

If ice cream student projects are your thing, perhaps you’d like a 3D printer?

Making Ice Cream With Heavy Metal

After his last project left him with an eleven-pound block of aluminum, [Jason] got to thinking of what most of us would in that situation: fresh made ice cream. His mind was on the frozen concoctions of the aptly named Cold Stone Creamery, a mall food court staple where a chilled stone is used to turn fresh ingredients into made to order sundaes.

[Jason] did the math and found that an eleven-pound chunk of aluminum can absorb a little over 67,000 joules, which is over twice the energy required to freeze 100 g of water. In place of water he would be using cream, condensed milk, and strawberries, but believed there was a large enough safety factor to account for the differences between his ingredients and pure water.

His first attempt didn’t go exactly as planned, but with his Flir One he was able to back up his theoretical numbers with some real-world data. He found that he needed to start the aluminum block at a lower temperature before adding his ingredients, and through experimentation determined the block only had enough energy to freeze 30 g of liquid.

In the end [Jason] was satisfied with the frozen treat he managed to make from the leftovers of his radial mill project, but theorizes that an ever better solution would be to use a brine solution and drop the aluminum block all together.

Of course, if putting food on a slab of metal from your workshop doesn’t sound too appealing, you could always go the NASA route and freeze dry it. Either method will probably make less of a mess than trying to print objects with it.

Print Tasty Treats With MIT’s Ice Cream Printer

Ice Cream Printer

Three MIT students decided that 3D printers just aren’t interesting enough on their own any more. They wanted to design a new type of printer that would really get young kids engaged. What’s more engaging to children than sugary treats? The team got together to develop a new 3d printer that prints ice cream.

The machine is built around a Solidoodle. The Solidoodle is a manufacturer of “accessible” 3d printers. The printer is enclosed inside of a small freezer to keep things cold during the printing process. On top of the machine is a hacked Cuisinart ice cream maker. The machine also contains a canister of liquid nitrogen. The nitrogen is used to blast the cream as it leaves the print head, keeping it frozen for the 15 minute duration of the print.

It sounds like the team ran into trouble with the ice cream melting, even with the liquid nitrogen added. For a single semester project, this isn’t a bad start. Be sure to watch the clip of the machine running below.

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Pumping Station: One Takes On The Machine

Part one and Part two of Hackerspace Pumping Station: One taking on the Scion challenge are up and ready for your viewing pleasure. The team at Pumping Station: One built a Tron themed bicycle that when setup properly, would churn ice cream that turned your urine neon in about 6 minutes by using dry ice and ethyl alcohol. Besides sounding not so tasty, and having a multitude of problems along the way, the project turned out the be a success. The question becomes, does it stand up to the last Hackerspace, NYC Resistor, who made a drink mixing slot machine? And how will both fair against the up and coming Musical Building by Crash Space?

[Thanks Deven]