Glacial ice for cocktails?

Factual Questions
1

I was once told that glacial ice is incredibly dense due to the massive amount of pressure of thousands of pounds of ice on top of it for extended periods of time. Sounds believable to me.

Also, I was told that this ice is hauled in by some Alaskan cruise ships and used in their cocktails. And that due to the density of the ice, it will endure a good long drinking session without melting.

Is any of this true or was I victim of a convicing tall tale? If it is true why doesn’t someone market this stuff? Even if it weren’t feasible to cost effectively ship it from arctic waters, how hard could it be simulate the conditions to produce it commercially?

[sub]Inspired while enjoying an otherwise pleasant cocktail with annoying hollow little commercial “icetubes” that melt in four minutes.[/sub]

2

I do not think any of the Dopers on this board have ever had the problem of their ice melting in their drink. I bet none of them have ever let an alcoholic beverage sit long enough for that to happen.

3

Here here…

4

No way. I never nursed anything in my life, much less a drink. I do ok with homemade icecubes, but those bags you get at the store suck!

After five minutes, you’re using your teeth as a sieve.

C’mon, I’m trying to build the better icecube here! For the benefit of all of humanity! Ok, for the benefit of the drinkers, at least.

5

Ok ok.
I am not sure if the glacier thing is true or not but I think it would be pointless. The problem with the ice is the storage. If they would just keep it really really col, then it would not melt so fast. The problem is the bar usually gets the ice out of a big freezer/ice maker in the back. The ice at the bar sits in their little bin all night, gradually approaching room temperature and therefore already starting to melt.
I am not sure if all bars are like this. The ones that are not, I am sure have less of a problem with their ice. Though all the bars I have seen always have some barback bringing ice to the bar all night. They need to keep it in a freezer up at the bar. The problem with doing that is the freezer would be opened constanly and probably would not be very efficient.

Also, regarding the crappy cylinder stlye comercial ice “cubes”:
Anyone want to back me up with the Physics of the whole thing? I would think that this is a stupid shape for an ice cube. Since 1) it is small; and 2)with the hollow center, it has much more surface area than a cube. So this damn thing is going to melt faster just be design. I think the ice makers realize it will also “freeze” faster and so they stick with this design because it saves them production costs. The bastards do not care about us.
Yes? No? Maybe?

6

Storage: Nope. Not a bit of ice will melt at 32 degrees fahrenheit or lower. The point (theoretically) of glacial ice is that there’s much more water crammed into the same space than a freezer cube, it takes longer to melt.

Re: Tube cubes: Right on 100% Quicker to freeze, quicker to melt! Most efficient to make, least efficient to use. My point exactly!

7

most of the cooling ice does happens as the ice changes state to water. It only increases one degree in temperature, but it has to absorb many times the number of btu’s water does when it changes temperature. If you could get ice to instantly flash to water, that would be the most efficient way to use it, so slowly melting ice is not more efficient but rather less efficient. Ways to speed up melting would be to increase the surface area (sylindrical ice has a greater surface area to mass ration than cubes. If you punch a hole in the ice, that increases surface area. If you could create ice that is tiny round beads, like the ice used in slushies, that would be the most efficient cooling possible short of chemical intervention. If you sprinkle salt on ice, you lower its melting point so that instead of keeping your drink at a relatively constant 32 degrees, it might keep your drink 20 degrees or less. But it would taste awful. Salted ice is used to create home-made ice cream. In the days before refrigeration, blocks of ice mixed with rock salt was the best way to chill something below 32 degrees. Hard frozen ice cream is around 20 degrees.

All ice has a little bit of air mixed with it. Air has virtually no cooling capacity, so a lot of it in a cube of ice means that you are only getting a percentage of the full cooling potential of a cube of that size. Glacial ice isn’t really denser than regular ice from the freezer, but it’s had time to lose the dissolved air through pressure. Less air, more cooling capacity, but also less surface area (the pits left behind by escaping air bubbles increase surface area). This makes the ice last longer, but also makes your drink cool down less efficiently. But if you drink rapidly, who cares how efficient the ice is?

8

There’s really two cases here:

a. You put ice in a warm drink, and want the ice to cool it off. Here, you want the fastest cooling possible, as gabbyhayes has described.

b. You put the ice in an already-cold drink, to make sure it stays cold. Here, you don’t necessarily want the ice to melt immediately, but just counteract the warming of the drink. A slow melt might be better, depending on how fast you drink, and how cold the drink already was.

In any case, the colder the ice is to start with, the longer it will last, and the more heat it will remove from the drink, as Bear_Nenno pointed out. If you start with ice at -20 degrees F, it will last much longer than ice at 31F, since the drink has to warm up the ice to 32F before it even melts. Of course, more energy is put into melting it than warming it up, but it still helps.

Back to the OP, glacial ice buried under tons of ice is under extreme pressure, but as soon as you extract it, it’s at normal pressure. Ice isn’t compressible, so it doesn’t get more dense, except for the effects of squeezing out whatever air was trapped inside.

Arjuna34

9

A few years back some young entrepeneurs here in Alberta were mining ice off one of the many (non-park) glaciers in the mountains and making a pretty good dollar. I think this was back when the Japanese economy ruled the world and they sold a lot of glacier ice to Japan. They ran up against the environmental bureaucracy and went out of business.
Another business attempt off the British Columbia coast to capture melting glacier water flowing directly off the glaciers into the Pacific was also quickly crushed by the government.

10

I just returned from a cruise to Alaska (including Glacier Bay and College Fiord) and didn’t see any ice harvested. Granted, that is a sample point of one. I hearby volunteer to go on a TM sponsored series of expeditions to acquire a statistically significant amount of samples.

I did see what was claimed to be glacial ice on the streets of Anchorage. It looked like what is left when the last of the snow melts in the gutter each spring with bits of dirt and cinder mixed in.

A fair amount of glacial ice has bits of mountain mixed in it, some of the ice is quite black. Even some of the chunks that appear white can be seen trailing a gray runoff into the bay as they melt. I would think ice floes from pack ice would be of higher quality (excepting Polar Bear scat) for drink mixing. I vaguely recall a vodka producer carving off this ice for use in production due to it’s alleged purity.

11

Some likely factors having a greater effect on “in a drink” melt times of ice than the “density” of the glacial ice:

The temperature of the freezer where said ice has been stored since it was in the glacier.

The fact that all the data taken to verify the claims is done by people drinking in bars. Those taking the most data have necessarily done the most drinking.

The temperature of the liquor.

The relative density of the folks who are willing to pay extra for ice that came from a glacier.

Tris

12

Drink beer and free your mind of these worries.

13

imho i dont think anyone in the business would ever use a slow melting icecube the logic behind it is the quicker the ice melts the less product you need to add i.e. booze, soda, wine it is a matter of economics

14

Natural glacier ice that I have personally seen was a dark blue. Let’s face it, there are some things in there you really might not want in your drink.
When I was on a tour of a professional ice-making company the manager pointed out that the difference between their ice and the stuff you get out of your refrigerator was air. He said that most professional ice companies pump the air out of their product making it clear. The ice that was coming out of his machines did look like sheets of glass. He said the air in your refrigerator ice was what made it opaque

15

I seem to recall that the Japanese fad for glacial ice was based on the relatively large amount of air trapped in the ice they were using, so that it caused a drink to fizz as it melted.

FWIW, increased pressure makes ice melt at lower temperatures.

16

FWIW, not enough to make a difference. It will while it is AT THE BOTTOM of the glacier, but in your drink, it doesn’t have the weight of the glacier still pressing on it.

And the effect is NOT what makes ice skating possible. The average human only weighs enough to lower the freezing point of water a minute fraction of a degree.

17

This is absolutely true. To clarify: Increasing the pressure on ice causes it to melt even though the temperature of the ice is <=0º Celsius. I did not mean to imply that this in any way affected the melting or temperature of ice in your drink. I included this bit of info simply to remind people that the lattice structure of water ice is peculiar and breaks down under pressure.

<aside> I sometimes use salted ice in my margaritas, rather than salting the rim of the glass. It does make for much colder drinks, and it tastes pretty good.</aside>

18

But wait. What is the purpose of an ice cube? To make your drink cold, right? You mix ice and room-temperature booze, and the ice chills the booze while the booze warms the ice.

The more surface area the ice has, the more contact it will have with the warm booze, therefore, the faster the booze will cool off. Hollow ice isn’t designed for keeping your drink cold for a long time, it’s designed to cool your drink off fast. After all, how long are you gonna nurse the thing? You want a cold drink, fast, and you’re gonna drink it fast.

19

I use dry ice in all my drinks. It’s much more exciting, AND it’s less filling than your regular water ice.

20

As I sit here with a nice bottle of Laphroaig, sipping it neat, as should be done, I’ll offer this tidbit in passing to those who indulge in alcohol that must be cooled to be palatable:

In order for ice to melt, it must absorb, IIRC, 32 joules per gram. This is without any temperature change. To raise that same gram one Celsius degree will only absorb 4.19 joules. So, in order to most effectively cool your drink, the ice must melt. For the sake of simplicity, as well as for keeping the ice away from my drink, let’s use a glass of ice water for a short example.

OK, let’s say you have a pint or so of water, which in the infernal metric system (since that is the one I know the figures for) is 500 mL. We’ll pretend that water has a constant density, since it pretty much does, and call that 500 grams of water. Let’s say that the water is at 20º C. You want it to cool down to 5º C.

At 4.19 J/g for each Celsius degree that you want to lower the water temperature, that means that you need to absorb 62.85 J of heat from the ice. To accomplish that simply from the ice melting, you need 1.96 g of ice. Hmmm, that sounds a bit low, maybe I’m incorrect in my recollections from 10th grade Physics. But you can see what I’m getting at, right?

Anyways, the point is that you will need less ice if it melts quickly, assuming that you want a cold drink, rather than a drink with ice cubes in it. Since the ice melts more quickly as the surface area in contact with the water increases, and less quickly as the temperature differential decreases, you want a shape that will gain surface area as it melts.

Now to switch over to a completely different field of knowledge that I happen to have, namely naval gunfire ballistics. The types of charges used in naval guns (the ones on the ship, personal firearms are never called guns) are classified by whether their surface area increases, decreases, or remains constant as it burns. The hollow cylinder shape is of the “remains constant” category. Shapes that increase in surface area have multiple holes through the center.

I guess it all comes down to what you want to do with your ice. The hollow cylinder shape seems well suited for water, where you want to cool the drink as quickly as possible, and don’t mind at all if it’s “watered down”. The standard cube shape seems better suited for use in cocktails where you don’t mind a little bit of watering down, but not too much, and you don’t necessarily need the drink as cold.

In summation, I’ll suggest two solutions. The first is to stick with drinks, like this fine single malt scotch here, which do not require any cooling to enjoy fully. The second, for those who aren’t as well off as I (not every occupation is as financially rewarding as convenience store clerk, it seems), is to simply down the damn drink more quickly.