Water-Bath Canning, Step by Step (PREVIEW)

by Le Parfait America

Short answer: Water-bath canning processes filled jars in boiling water to seal high-acid foods (jams, fruit, pickles, acidified tomatoes) for shelf storage. You need a water-bath canner or a large deep pot with a rack, a jar lifter, Le Parfait Super Jars or Super Terrines, a fresh rubber gasket for each jar, and a tested recipe. Fill to the headspace the recipe specifies, process for the full time it specifies, then cool and check the seal. This guide walks through every step.

Water-bath canning is the method most home canners learn first, and it is the method Le Parfait jars are built for. It works by heating filled jars in boiling water: the heat drives air out of the jar, and as the jar cools the rubber gasket and wire bail pull the lid airtight, sealing the contents for shelf storage. This guide is a complete walkthrough of how to water bath can, written for beginners. For the bigger picture of where this fits, start with our Canning 101 beginner's guide.

Water-bath canning is for high-acid foods only

Before anything else, the one safety rule: water-bath canning is for high-acid foods only. That means most fruits, jams and jellies, pickles, and properly acidified tomatoes. Low-acid foods (plain vegetables, beans, meat, poultry, and plain broth) are not safe to water-bath can. Those require dedicated pressure-canning equipment that reaches a higher temperature. If you are not set up for that, refrigerate or freeze those foods instead. Le Parfait jars are made for the water-bath method and high-acid foods, never for pressure canning.

What you need

  • A water-bath canner or a large deep pot with a rack. The pot needs to be deep enough to cover the jars with at least an inch of water and still leave room for a rolling boil. The rack keeps jars off the bottom so water circulates underneath them.
  • A jar lifter. This is the one tool worth buying. It grips hot jars by the neck so you can lower them in and lift them out without burning yourself or tipping them.
  • Jars: Le Parfait Super Jars or Super Terrines, sized to your batch (the 1L / 32 oz is the all-purpose workhorse; the wide-mouth Super Terrine is the line built specifically for canning).
  • A fresh rubber gasket for each jar. Use a new Le Parfait gasket every canning session.
  • A clean cloth for wiping rims, and a tested recipe for the correct acidity, headspace, and processing time.

These are not antique bail jars. The glass is heat-resistant, the hardware is stainless steel, and the natural rubber seal is replaceable, so you fit a fresh gasket for each canning session and reuse the jar for years. (In everyday, non-canning storage, a gasket lasts for years of reuse; for canning, replace it each session.)

Step by step

  1. Prepare your jars. Wash the jars, lids, and bails, inspect every jar for chips or cracks, and keep the jars hot until you fill them so they do not crack from a sudden temperature change. Our guide to preparing jars for canning covers cleaning and sterilizing in full.
  2. Fill with a tested recipe. Ladle in your prepared food, leaving exactly the headspace your tested recipe calls for (the gap between the food and the rim). Headspace matters for the seal, so follow the recipe rather than filling to the top.
  3. Remove air bubbles and wipe the rim. Slide a non-metal utensil down the inside of the jar to release trapped air bubbles, then adjust the headspace if it dropped. Wipe the rim and the sealing edge clean with a damp cloth; any residue can prevent a good seal.
  4. Fit a fresh gasket and close. Place a new Le Parfait rubber gasket on the lid, set the lid on the jar, and close the wire bail. A fresh gasket every session is what makes the seal reliable.
  5. Lower the jars into boiling water. Using the jar lifter, lower the closed jars onto the rack in your canner. The water should cover the tops of the jars by about an inch. Bring it back to a full rolling boil before you start timing.
  6. Process for the full time your recipe specifies. Keep the water at a steady rolling boil and process for the entire time your tested recipe gives. Do not cut it short, and do not guess: the processing time is set by the recipe for your specific food and jar size. (If you live at a higher altitude, follow your recipe's altitude adjustment.)
  7. Remove and cool undisturbed. When the time is up, turn off the heat and lift each jar straight up with the jar lifter. Set the jars on a towel or rack, spaced apart, and leave them undisturbed for 12 to 24 hours. You may hear them seal as they cool. Do not press, tilt, or retighten anything while they set.
  8. Check the seal. Once fully cooled, confirm each jar sealed before you store it. If a jar did not seal, our canning troubleshooting guide covers what to do (refrigerate and use it soon, or reprocess).
  9. Label and store. Label each sealed jar with its contents and the date, and store it in a cool, dark place. Properly canned high-acid food keeps on the shelf for a year or more.

A few things that make the difference

  • Follow a tested recipe, not a guess. The recipe sets the acidity, the headspace, and the processing time. Those three together are what make water-bath canning safe. When in doubt, follow the recipe rather than improvising.
  • Fresh gasket, every session. A new Le Parfait rubber gasket each time is cheap insurance for a reliable seal.
  • Keep jars hot before filling, and let them cool slowly after. Sudden temperature swings are what crack jars. Hot food into hot jars, and no cold drafts on the cooling jars.

Where to go next

Need jars or gaskets? Browse the preserving jars collection, pick up fresh rubber gaskets, or start with which Le Parfait jar and size you need.

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