This is the specialised equipment needed for "pressure canning", as you can see it's an oversized pressure cooker, big enough to hold about 7 big jars.

Low acid foods require processing at a temperature of 116 degrees centigrade for safe preserving to avoid the potentially fatal poisoning by botulism.

You do need a bit of specialised equipment to achieve these temperatures, but the process is simple. You can even re-use the jars. All you need is a recipe, and for safety's sake, new lids and a "pressure canner".

We recommend that even if you are just curious about "pressure preserving" that you download the Presto Manual. This publication is a lot more than just an ordinary manual, it contains preserving safety information, and many recipes.

• The easy-to-read gauge automatically registers a complete range of processing temperatures.
• Air vent/cover lock allows pressure to build up only when the cover is closed properly and prevents the cover from opening until pressure is safely reduced.

Presto® Pressure Canners also double as water bath canners for preserving fruits, jams, jellies, pickles and salsas.

Canners are constructed of extra-strong, warp-resistant aluminum and are suitable for use on regular and smooth-top ranges. Includes cooking/canning rack and complete instruction and recipe book.

This Presto Pressure Canner is 280mm high, internally, and 310mm wide internally.

Mason Jar Capacity: 24 Half-Pints, 20 Pints, 7 Quarts.

23-Quart liquid capacity (21.8 litres)