Crystal clear ice cubes
Hot Water Is Crucial To Get Crystal Clear Ice Cubes
Freezing hot water results in crystal-clear ice cubes because heating water removes the impurities and elements, like air and minerals, that are naturally present in water.
These elements get trapped as cold water freezes, resulting in cloudy ice. According to former bartender Millie Pham, boiled, distilled water creates the clearest cubes possible.
Distilled water is processed to remove minerals, salts, and other impurities, so boiling it and pouring it directly into an ice cube tray or mold will get you transparent cubes.
Pham mentions that a clear ice mold is a big help. Clear molds have a design that allows the water inside to freeze from one direction, not from all 360 degrees like regular ones.
When water is frozen in one direction, any existing air bubbles are slowly forced out of the water, leaving behind ice you can see through.