Solid Ice

[sleddriver]

Where I live, there are two seasons: SUMMER and February. As such, keeping a drink cold outdoors involves an insulated mug and ice. For the former, I prefer the large plastic double-walled versions made by Tervis. They don't heat up as much as the metal versions when in the Sun.

With regards to ice, standard ice from the freezer has air frozen into it, turning it cloudy. As such, it isn't as solid as say a clear block of ice. The result being it melts faster, dilluting a drink faster and doesn't last a long. I found a set of 'ice ball molds' on sale and tried them. Much larger than a standard ice cube, they do last longer, however they don't make SOLID ICE either.

So last year I began experimenting with making large blocks of solid ice. I found a small cooler that fits in the freezer. I must say it works very well. This works by slowing the rate of freezing from all directions but one, in this case the top. Therefore, the ice freezes from the top down, forcing air out in the process, towards the cooler bottom.

Drinks stay colder longer, don't dilute as fast, and I'm not regularly having to refill with ice. Keeps the iced tea from getting watery during the HEAT.

Stay Cool....

http://www.alcademics.com/2010/08/a-homemade-giant-crystal-clear-ice-cube-tray.html

 

[Food Scientist]

Boiling the water first to remove dissolved gases helps.

 

[Whipcitywrencher]

Pretty cool stuff.

 

[Leo99]

Every bar I went to in Japan last month had the same type of ice cubes. They were a very dense cube and melted slowly.

I've been to bars in the USA that use very large ice balls to reduce the surface area and slow the melting rate.

 

[oldhp]

Science.......I should've paid more attention in school.

 

[Nyogtha]

Ice always forms from the top down. It's due to difference in density, water being more dense in liquid form than solid form, an uncommon phenomenon due to the strong hydrogen bonding in water.

If water didn't freeze from the top down life (as we know it) probably would not exist on this planet.

 

[sleddriver]

If you eliminate the cooler, you won't achieve the same results.

 

[Rand]

silicone ice cube trays do the same thing.

They make bigger ones for drinks and works 95% as good without any fuss.

 

[Ducked]

Originally Posted By: sleddriver

With regards to ice, standard ice from the freezer has air frozen into it, turning it cloudy. As such, it isn't as solid as say a clear block of ice. The result being it melts faster, dilluting a drink faster and doesn't last a long.


I'd bet the same mass of ice at the same temeperature has the same cooling effect, whether its got bubbles in it or not.

 

[Johnny2Bad]

Originally Posted By: Ducked
Originally Posted By: sleddriver

With regards to ice, standard ice from the freezer has air frozen into it, turning it cloudy. As such, it isn't as solid as say a clear block of ice. The result being it melts faster, dilluting a drink faster and doesn't last a long.


I'd bet the same mass of ice at the same temeperature has the same cooling effect, whether its got bubbles in it or not.


True, the mistake is that many assume mass = volume, in other words two cubes of the same physical size, one with and one without air, will melt at different rates. If you were to weigh them, the one incorporating air would weigh less (ie less mass).

You could also use cubes of differing physical size (identical mass, but differing volume) with / without air, and they would melt at the same rate, as you suggest. The problem is the larger volume cube displaces more water (or alcohol, or coke, etc) which affects the amount of (wanted) liquid in the glass negatively, and therefore increases dilution when it does eventually melt. This is essentially due to the fact that the glass has a fixed and limited capacity.

On a lake or pond, it wouldn't matter. You won't notice that the frozen height of the pond is a few mm higher if it froze quickly and incorporated more air. What would matter is the strength of that ice, making an educated decision as to whether it can support your weight necessary.

Somewhat related, is the myth that hot water freezes faster than cool water. The evaporation rate is higher with the hot water, so what you actually end up with is a cube of smaller volume. That will freeze quicker but it's not because it's hot, exactly ... if you adjusted the volumes of water to be equal mass cubes (ie use less cold water), they would become frozen at the same time.

The area exposed, which was assumed to be equal in all of the above, also affects the rate of freezing. The popular YouTube video of someone throwing water into the air and it freezing almost immediately is simply due to the size of the droplets of water when thrown into the air. Put the bowl or pot outside with the same amount of water and it will take some time to freeze. Also the videos imply it's due to how cold the ambient temperature is, and it plays a role, but it does not have to be particularly cold (below freezing) to pull it off.

 

[sleddriver]

Originally Posted By: Ducked
Originally Posted By: sleddriver

With regards to ice, standard ice from the freezer has air frozen into it, turning it cloudy. As such, it isn't as solid as say a clear block of ice. The result being it melts faster, dilluting a drink faster and doesn't last a long.
I'd bet the same mass of ice at the same temeperature has the same cooling effect, whether its got bubbles in it or not.
The same mass, yes. But not the same volume. As pointed out above, a block with air frozen in it is lower in mass than one without. Further, once the outer layer has melted to allow the liquid access to the hollow tubes, it will usually crack & cleave, exposing more surface area, lowering the melting time. Whereas, a solid block of ice has no hollow tubes. There is no frozen entraped air to speak off.

 

[PimTac]

The composition of the ice is the key.

Some of you may remember the old ice dispensers that were on roadsides. They had bagged ice and block ice. As kids we would buy a block of ice and ride it down a paved slope for fun. In the middle of summer it was amazing to see how long that block of ice lasted.

 

[sleddriver]

I continue to make and use solid, clear ice using the method discussed earlier. Now that it's > 100°F, outdoor drinks stay cooler longer and take far longer to dilute. Furthermore, a long rectangle about 1-1/2 x 1-1/2 x 5" appears ideal for a tall container. I've also found I can score larger blocks with a serrated knife, then cleave them off using a cleaver + wooden mallet.

On another note, I experimented with dry ice a few Summers ago to preserve ice in an ice chest during the intense Summer heat. Everything inside stays colder longer and you don't need as much ice. Going the distance is really helpful as the first drinks are consummed then replaced with warm ones again and again.