12 Lifesaving Canning Rules

September 24, 2015, by Ken Jorgustin


When it’s that time of year for canning your garden bounty, or when canning anytime of year while taking advantage of sale prices on food, before you pull out your canner and fire up your stove, first take a look at these 12 lifesaving canning rules…

If done properly, canning is entirely safe; however certain precautions should be taken. Generally, I will say that the most important thing to remember (especially for newbies) is to follow the instructions of a modern canning recipe exactly – and those from a reliable source. Canning recipes and instructions are designed to provide a wide margin of safety.

For example, Ball Complete Book of Home Preserving


Safety Rules Of Canning

1. Don’t use jars larger than a quart. Home canning technology cannot guarantee that larger quantities will be sufficiently heated through for enough time. Rather, the food on the outside will overcook, while that on the inside won’t get hot enough for food safety.

2. A water-bath canner may only be used for high acid foods such as tomatoes, fruits, rhubarb, sauerkraut, pickles, and jams/jellies. A pressure canner MUST be used for low acid foods including vegetables, meats, and stews.

3. Use only modern canning recipes from reliable sources (especially when first starting out).

4. Never reuse jar lids. Used lids aren’t reliable for sealing correctly. If a screw-on band is rusty or bent, it won’t work right and should be discarded and replaced. That said, you might consider purpose-designed reusable Tattler lids.

5. Don’t use antique or ‘French’ -type canning jars. They aren’t as safe as the modern, regular ‘Ball, Kerr’ type.

6. Check the jar rims carefully every year by running your finger over the top of the rim and checking for nicks. Even the tiniest nick makes the jar unusable for canning. A nicked jar rim won’t seal reliably.

7. Raw pack is not safe for certain foods: beets, all kinds of greens (spinach, etc.), white potatoes, squash, okra, a tomato/okra combination, and stewed tomatoes.

8. You must allow the correct amount of space (head-space) between your food, together with the liquid that covers it, and the jar lid (follow the recipe instructions).

9. Do not begin counting the processing time until after the water in the canner comes to a rolling boil (if using the water-bath method), or until after steam has vented for 10 minutes AND until the pressure gauge has risen to the recommended pressure after placing the weight on the vent pipe (if using a pressure canner).

10. Process the full recommended time (and at the recommended pressure if using pressure canner).

11. Lift out each jar individually using a jar lifter; keep it upright and not tipped.

12. If a jar did not seal, discard the lid, check to see if the jar rim is chipped (discard jar), check for food residue on the rim (clean), put on a new lid, and reprocess. Or consume the food and/or put in the refrigerator as you would any other leftover food for later consumption.


Some recommendations gathered from The Encyclopedia of Country Living