Have you ever noticed that a completely transparent type of ice is always served in the premises, while the cubes you prepare at home are always opaque and cloudy? This is due to the gases dissolved in the water being trapped by force in tiny bubbles, or it happens when the water freezes in a way that does not allow the formation of large crystals. Due to impurities, opaque ice is weaker and melts faster than clear ice. The "ice experts" have devised several methods to prepare ice at home as perfect as the one in the restaurant. Here's how to do it!
Steps
Method 1 of 4: Boil the water
Step 1. Use impurity-free water
This method is used to remove most of the air and impurities from the water before freezing, so it is better to work directly with distilled water. The bottled one or the one purified with reverse osmosis is also fine.
Step 2. Boil the water twice
Boiling removes air bubbles from the liquid, promoting a stronger bond between the water molecules upon freezing.
- After the first boil, let the water cool down. Then bring it to a boil again.
- Keep the water covered as it cools to prevent dust from settling on the surface.
Step 3. Pour the water into the ice cube tray (or mold of your choice) and then cover it with cling film to prevent the liquid from becoming contaminated with dust
If you really want an amazing effect, make some larger cubes and ice balls. There is nothing better than serving a drink with a single piece of ice!
Step 4. Place the pan in the freezer
Wait a few hours for the water to freeze.
Step 5. Remove the tray from the freezer and carefully peel off the clear cubes
Method 2 of 4: Freezing from top to bottom
Step 1. Get a small cooler bag
You don't need a special bag, the one you use to keep drinks cool during outings is also fine, but if it's too big you won't be able to fit it in your freezer. It is used to isolate the ice cubes, so that they slowly freeze from top to bottom.
Step 2. Lay the tray (or whatever mold you choose) at the bottom of the cooler, leaving it open at the top
If possible, use a large cube tray, or a set of rectangular silicone or plastic molds.
Step 3. Fill the tray (or molds) with water
People who use this method often claim that they get great results even with tap water, so you don't have to use distilled or boiled water.
Step 4. Pour some water into the cooler to completely surround the tray or molds
This step serves to better isolate the cubes, preventing cold air from starting to freeze the water from the side or from the bottom.
Step 5. Place the open cooler bag in the freezer
Make sure the temperature stays between -8 ° and -3 °. Wait 24 hours.
Step 6. Remove the cooler bag from the freezer and, gently, take the block of ice in which the tray is stuck
The ice will likely have a slight opaque layer on top, but the rest should be completely transparent.
Step 7. Peel off the ice blocking the tray or molds, then collect the cubes
Step 8. Leave them at room temperature for one minute so that the top opaque layer melts
You now have perfectly transparent cubes.
Method 3 of 4: Freezing at High Temperatures
Step 1. Set the freezer temperature to around -1 °
It should be the highest temperature you can set. If you don't want to raise the temperature in the whole freezer too much, you don't have to change it: just place the tray on the top shelf.
Step 2. Fill the tray (or molds) with water and place it in the freezer
Wait 24 hours. Slow freezing should expel any gases or impurities in the water, creating perfectly clear ice cubes.
Method 4 of 4: Freezing from Below
Unlike the previous one, it is a method that allows you to create transparent ice cubes without any cracks, except for the first time you run it. It also works if you put the water in the tub directly from the tap. Air pockets can be eliminated by freezing the water from the ace upwards. This can be achieved by placing the lower part in contact with something very cold. It is preferable that this something is a liquid because, in that way, it can completely cover the bottom and dissipate the heat quickly. A practical liquid to use to cool the pan is salt water.
Step 1. Fill a bowl with water, add lots of salt to keep it from freezing and then put it in the freezer
Be careful not to put too little water in the bowl or the process will release enough heat to heat the salt water to 0 ° C before the ice cubes are fully formed. The lower the temperature in the freezer, the higher the salt concentration must be to prevent it from freezing. With experience, you will be able to know how much salt you need for the temperature you normally set your freezer to.
Step 2. Leave the salted water in the freezer for at least 3 hours so that it can cool down properly
Step 3. Boil some water, then let it cool to get rid of the micro bubbles
Step 4. Take the saltwater bowl out of the freezer to prevent the water in the bowl from freezing from above
Step 5. Fill an ice cube tray with water, then place it over the salt water in the freezer, which is denser than fresh water
You will get ice free from air bubbles and without any cracks, as the process prevents air bubbles from forming during freezing.
Step 6. Return the tray to the freezer to prevent the ice from melting
Step 7. Return the saltwater bowl to the freezer so you can skip step one the next time you want to make clear ice
Advice
- Use a stainless steel pot to boil the water instead of an aluminum one.
- There are commercially available insulated trays for making ice if you can't find a cooler bag small enough to put in the freezer.
