Clearly a Failure
October 29, 2008
There are various methods people use to make the clearer ice. To remove the air bubbles that make ice cloudy, people suggest boiling or refreezing the water. I decided to give a few options a try to see what worked best. But as we'll see, my results are less than conclusive.
Using individual sized apple sauce cups (these are great large cubes for drinking whisky, as you don't want the ice to melt too rapidly and water it down) I froze the following into ice:
- Control ice- regular ice poured from the Britta filter, probably two days old
- Re-frozen- above style ice cubes, melted and refrozen
- Boiled in pot for about 10 minutes
- Microwaved for about three minutes of boiling
Then I lined up all the ice in order of most clear to least. I had two of each style of ice, and my results were: Control, Control, Boiled, Microwaved, Refrozen, Microwaved, Refrozen, Boiled. None of the ice was totally clear. And the control should have been the least clear, not the most.
So... that didn't work at all. I will need to repeat this experiment. Any ideas on what I did wrong? the cups in the picture are upside down, so the most air/cloudiness was on the bottom of the container. Perhaps I need to pour it slowly into the tray to avoid adding air at that point? Drip it through a filter? Use a colder temperature? Suggestions gladly welcomed.
An index of all of the ice experiments on Alcademics can be found here.
http://en.wikipedia.org/wiki/Purified_water
You want purified water. Water that's been distilled or deionized to remove as many minerals as possible. Boiling the water just concentrates the minerals in the pot. (Unless you are capturing the steam, i.e. the distilled water). You want as close to H2O as possible- the stuff in the grocery store that's for your iron, if you ever ironed the pink shirt. ;) (usually labelled "distilled water")
A water vending machine in front of a grocery store can provide very pure water (check the settings on the machine- don't choose "drinking water", choose "purified water"). Water Vending machines are actually purification plants on a small scale. The have carbon, UV, reverse osmosis, and de-ionization filters inside.
Clear flavorless ice will be yours.
Posted by: Martin | October 29, 2008 at 11:50 AM
I've read that double-boiling helps, a quick google showed that solution several places. I've also read that the reason larger machines get clear ice is motion, basically the water is always slightly moving or vibrating until the point it freezes. I'm not sure how easy it would be to rig something like that up in your own freezer, but just thought I'd throw it out there.
Posted by: DrinkPlanner | October 29, 2008 at 12:56 PM
Did you filter the water through a Brita or something first? I've heard that helps.
Distilled water would definitely be the purest though, and least likely to have any nucleation points.
Posted by: eatyourbeer | October 29, 2008 at 01:54 PM
You should try creating the ice cubes in layers, starting with just a small amount of water in your tray. Then add a little more water and refreeze. Repeat until you've reached the desired size. Let me know how it works out for you.
Posted by: Ben Requena | October 29, 2008 at 02:01 PM
I don't know if we're freaks, but we get freakishly clear cubes using our silicone ice trays and tap water.
Posted by: Cior | October 29, 2008 at 02:29 PM
I'm using those silicone ice trays too(if designed for baking lousy-crust muffins). Actually look like yours in the photo. Takes a steady hand to get in the freezer w/o spilling. Ours are near crystal clear, but start with filtered ice cold water.
Posted by: eas | October 29, 2008 at 10:37 PM
Glad to hear I'm not the only cocktail blogger on the quest for clear ice at home.
Here are the variations I've tried:
Tap water (control)
Brita water
Brita water thawed and refrozen
Brita water boiled
Brita water boiled twice
Distilled water
Distilled water boiled
Distilled water boiled twice
Distilled water thawed and refrozen
All of the above result in cloudy cubes but the water straight from the Brita seems best in my experiments as well.
The source of the cloudiness at the bottom of the cubes, in my experience, seems to results from the fact that the ice freezes from the top down. When this happens it creates a barrier for the gasses to escape. As the water gets close to freezing the remaining gas is forced out of suspension but has nowhere to go, thus tiny bubbles.
I use Tivolo cube trays but found they work best after they've been through the dishwasher. They had a very thin layer of something on them that was adding to the milkiness of my cubes.
Posted by: Reese | October 30, 2008 at 07:03 AM
To commenter EAS: do this..take a small flat baking sheet, or even a stiff carboard, place the silicone tray on what you have aquirred...
Then fill with water. This way you will have stability travelin' to the freezer ! yay !
Posted by: Victoria | October 30, 2008 at 04:31 PM
Thanks everybody for the tips. Round two coming soon....
Posted by: Camper English | November 01, 2008 at 08:26 PM
On a recent episode of "Food Detectives" on the Food Network they puzzled this as well. While they didn't go into nearly as much detail as I'd like (they never do). They method they showed, which "appeared" to work reasonably well in relatively small ice cubes, was to both start with distilled water, and then boil it, allow that to cool, and boil it again.
I've also heard that constant slight vibration during freezing is suppose to help?
Posted by: Robert Hess | November 03, 2008 at 03:27 PM