WATER BATH METHOD

This is my favourite way to preserve fruit or tomatoes. It’s the most timeefficient and safest method; there’s no hot liquid to deal with and minimal contact with hot jars. The best part is there’s no need to sterilise the jars, or in some cases even cook the produce first.

I use a water bath heat-processing preserver called Fowlers Vacola that I picked up second-hand and is plugged into the wall much like a large kettle. If you have a lot of fruit to preserve over the season, it’s worth the investment.

You can also make your own water bath unit. You’ll need a large pot, tall enough for the jars to be submerged in the water. Place something (such as a cake-cooling rack) in the base for the jars sit on, so they’re not in direct contact with the bottom of the pot.

How to: Fill jars with cooled compote or pack snugly with raw halved/quartered fruit and cover with cold water, diluted fruit juice or light sugar syrup. Top up the liquid to within 1cm of the top of the jars.

Gently tap each jar on the bench to remove air bubbles, sliding a butter knife around the inside of the jar if needed to release any large air pockets. Wipe the rim of the jars with a clean cloth. Screw the lids on hand-tight (don’t over-tighten, as this can break the seal).

Place the jars in the water bath, ensuring there’s a little space between each for the heat to circulate. Fill the bath with cold water to cover the top of the jars by 1-2cm. (If you’re using a pot that isn’t tall enough to cover the jars, the water can come to within 3-4cm of the top of the tallest jar).

Cover with a lid (if possible) and switch on/ place on a stovetop over a moderate heat. Once the water reaches a gentle simmer, turn the heat to low for 10 (for jars of less than 500ml) to 15 minutes (for jars up to 1 litre).

Switch off/remove from the heat. Use tongs to transfer the jars to a wooden board, or remove some of the water and use oven gloves to carefully lift the jars from the pot. Once the jars are completely cool, check the lids, making sure they’re concave or the button has popped down, indicating that the lid is vacuum-sealed correctly.