The distinguishing feature of distilled water is that it is completely free of anything other than the essential base elements, hydrogen and oxygen. Therefore, it has none of the minerals of bottled water, none of the potential contaminants of tap water and no discernible taste. While distilled water does have a handful of culinary uses, making it consumes a lot of energy for the eventual yield.

Two options present themselves for making distilled water at home. By far the easier is to invest in a distilled water machine. Similar in appearance to a coffee maker, an electric distiller heats tap or tainted water, converts it to steam and collects pure distilled water in a jug.

For minimum chance of contamination, look for one with a glass carafe, as this type is easier to sterilize and doesn’t retain other cooking aromas. Distilled water machines can be expensive, but they make the collection process impossible to misjudge.

Unleashing skills that may have remained dormant since high school science fair, cooks can distill water on the stove top by exploiting the fact that water will convert to steam at 212 degrees Fahrenheit, leaving minerals and impurities behind.

  • Find a big steel pot with a slightly larger lid — ideally
    made of heatproof glass so that you can see through it — and without a steam vent.  
  • Pour in the water to be distilled but no more than a third
    of the way up the pot as the process needs room for steam, not bubbling water.
  • Place a glass bowl inside the bigger pot, using a metal or
    ceramic trivet to keep it from touching the base. The snugger the bowl fits
    inside the pot, the better, but there should be room at the sides for steam to circulate.
  • Turn the big pot’s lid upside down so that its handle is
    inside the pot, and start the stove.
  • Bring the water to the boil, turn it down to a simmer and
    start covering the lid with ice cubes. The steam will condense as it comes into
    contact with the cold surface, and distilled water will run down the slightly
    curved lid, collect at the handle and drip down into the bowl.
  • Monitor the pot to make sure it doesn’t run dry, and
    replenish the ice regularly as it melts.
  • Turn off the heat and carefully remove the lid, watching out for escaping steam as well as melted ice dripping into the
    distilled water.
  • Carefully remove the glass bowl, which will be hot. The
    liquid inside is distilled water.  

Distilled water has some advantages compared to tap or mineral water.

  • Distilled water is useful for
    soaking and cooking dry beans, which might otherwise take longer to cook in tap water, because of the
    presence of mineral deposits.
  • Pickling and canning are difficult with a hard water source, so distilled water provides a solution. For canning, using
    distilled water is also a safeguard against water-borne bacteria that could
    ruin the process.
  • Brewing some teas, such as green or jasmine tea, with
    distilled water also yields a cleaner taste than if you use mineral or tap water.