Alcademics

Tag: ice clarity

  • Another Clue to Ice Clarity: Slow Freezing Like a Japanese Pond

    The other night a friend of mine told me that she read something about clear ice, which as you may recall is a topic of interest of this blog. Naturally I forgot what she said (we were at a bar, remember) but the next day I found the following email I had sent to myself:

    "Clear ice old japan sawdust"

    The amazing thing is that when you put that into Google the very first story it comes up with is what I assume is the exact thing my friend was talking about. In this story on natural ice (popsicles) in Japan, a person in the story gives a quote that could prove useful. 

    Masao Yoshiara, the fourth-generation president of the company, said: "In Nikko, the daily lowest temperature in winter averages around minus 10 C, ideal for making crystal-clear ice.

    "If it's colder than that, ice can be made quickly but it is not solid enough. Here, ice grows 1 centimeter thicker a day. When ice becomes about 15 centimeters thick over half a month, we cut out ice blocks. If an ice block is thicker than that, it contains cracks."

    Minus 10 degrees Celsius is 14 degrees Fahrenheit. I don't know the temperature of my home freezer, but it's worth investing in a thermometer to find out. Perhaps slow freezing equals clearer ice.

    The other factor we'll have to consider about pond ice is that the bottom never freezes. Thus the air that is a major factor in cloudy ice is still in the warmer water below the surface layer of the ice.

    This is another strategy I've been considering in attempting to get clear ice in the freezer: if I place a good insulator at the bottom and sides of the water container that doesn't cool down nearly as fast as the water (for example a super thick glass bowl, or a pan of ice that sits on a stone surface), will that cause all the air in the water to migrate to the bottom and freeze last?

    This reading inspires a lot more ice experiments to come. I'm glad I emailed myself from the bar.

    An index of ice experiments on Alcademics can be found here.

  • Does Freezing Water in Layers Make Clear Ice?

    Here's a new edition in my ongoing ice experiments. So far, there experiments have been:

    With successes in:

    So far my conclusions have been that (at least with my San Francisco water), temperature and filtering have less of an effect than trapped air that migrates to the center of the freezing cube. Thus I am trying to minimize this effect.

    In this experiment I froze ice in layers in small lasagna pans to see if we had a maximized surface area, hopefully no air would get trapped in the ice and form cloudy parts. Apparently some commercial ice machines such as Kold Draft spray an upside-down mist of water in layers, so this would be the home approximation of that.

    I tried this experiments with tiny layers, medium layers, and large layers in the same sized pan, the difference being that I added more water per layer. I let the water freeze before adding another layer.

    As you can see, none of the layers turned out clear:

    (Tiny layers, medium layers, and large layers left to right.)

    The small sized layers were made only adding a couple of ounces of water at a time, so I can't get much smaller layers than these unless I use a spray bottle. 

    We'll have to call this one a failure. Freezing water in layers does not appear to make clear ice, just ice with smaller layers of trapped air.

    Below is a closeup of the layers for your ice ogling enjoyment.

    Threelayerscloseup

    An index of all of the ice experiments on Alcademics can be found here.