Preserving Blackberries in Jams and Fruit Leathers

A Glut Worth Planning For

By late August, most British hedgerows are sagging under the weight of brambles. One afternoon's picking can easily fill a couple of supermarket bags, and that is exactly when the kitchen starts to feel like a small factory. Jam and fruit leather are the two most forgiving ways to deal with a blackberry glut: both keep for months, both need no specialist equipment, and both capture that deep, faintly winey flavour far better than a punnet in the fridge ever will.

A few rules before you fill your tubs. Pick berries that come away with almost no tug — if you have to pull, they are not ready, and under-ripe fruit makes a dull, bitter jam. Leave the low-hanging clusters alone and work at waist height and above; this is both cleaner and safer, since berries near the ground can be contaminated by animal droppings. Take a mix of firm ripe fruit and the softest, sweetest ones, as the softer berries bring colour and flavour while the firm ones supply pectin.

Sort, Clean and Freeze What You Can't Use Today

Tip your haul into a large bowl of cold water with a teaspoon of salt. After ten minutes, most small wildlife will have floated free. Lift the berries out rather than pouring, so grit and debris stay at the bottom, then drain on a clean tea towel and pick out leaves, stalks and any fruit that has gone brown or mouldy.

If you have more than you can process in one sitting, freeze it. Blackberries freeze beautifully in bags or tubs, and freezing has a happy side effect: ice crystals rupture the cell walls, so thawed fruit releases more juice and gives a better set. Weigh the fruit into 1kg batches before freezing, so you can pull out exactly the amount a recipe needs without guessing.

Blackberry Jam That Actually Sets

Blackberries are low in pectin, which is why so many homemade batches end up as syrup. Two fixes: add lemon juice, and pair the fruit with a little apple. Windfalls or a couple of grated Bramleys work brilliantly and disappear into the flavour.

• 1kg prepared blackberries
• 2 cooking apples, peeled and grated (or 2 tbsp lemon juice)
• 1kg preserving sugar, or granulated with a sachet of pectin

Warm the fruit gently with the apple and a splash of water until it collapses and the juice runs — about 15 minutes. Add the sugar off the heat and stir until completely dissolved; if you can feel grains on the spoon, keep stirring. Then bring it to a rolling boil that cannot be stirred down, and hold it there for 10–15 minutes.

Test the setting point by dropping a teaspoon onto a cold saucer from the freezer. Let it cool for a minute, push it with your finger — if it wrinkles, you are there. If not, boil for another three minutes and test again. Pot into warmed, sterilised jars, seal, and label once cool.

Fruit Leather: The Chewiest Way to Store Sunshine

Fruit leather is the answer when you want something that fits in a coat pocket. Simmer 1kg of blackberries with a splash of water until soft, then push the pulp through a sieve to remove the seeds. This is tedious but non-negotiable; unsieved leather is gritty and unpleasant. Sweeten the smooth purée to taste with honey or sugar, and add a squeeze of lemon to sharpen it.

Line a flat baking tray with baking parchment and spread the purée about 3–4mm thick, tilting the tray to even it out. Dry it in an oven on its lowest setting — around 60°C — with the door propped slightly open, for four to eight hours. A dehydrator at 55°C does the same job in roughly six. It is ready when the surface is dry to the touch and the sheet peels cleanly away from the paper without sticky patches.

Roll the sheet up, parchment and all, and slice into ribbons with scissors. Store in an airtight jar or a tin.

Jazzing It Up with Other Hedgerow Fruit

Blackberries play well with almost everything else ripening alongside them. A handful of elderberries deepens the colour of both jam and leather, though never use them raw. Rosehips, sieved and added to the pulp, bring a lovely tartness. Damsons, sloes and haws all work in small quantities. For a spiced version, tie a cinnamon stick and a few cloves in muslin and fish them out before potting. A little vanilla in the leather makes it taste absurdly good.

Storing, Labelling and Knowing It's Good

Jam keeps best somewhere cool and dark, and will hold its quality for at least a year — the sugar and acid do the preserving. Fruit leather lasts six to nine months in a sealed container, longer in the fridge. Label everything with the fruit and the date; memory is a poor archivist by November.

Once opened, a jar of jam belongs in the fridge. If you spot mould on the surface, discard the whole jar rather than scooping it off. Leather that has gone tacky can be returned to the oven for another hour. Get either of these right and you will spend January eating late summer on toast — which is the whole point of a hedgerow glut in the first place.