How To Use


Over recent years the UK has seen a revival in jam making, as we’ve got back in touch with our heritage of preserving the bounties of summer and autumn. Whether you’ve been making jam for years or this is your first time, we hope you’ll find our list of top tips a helpful aid to making great jam.

  • Source by season. Fruit is never more flavoursome that when it’s fresh, ripe and in season. Ensure your fruit is clean and dry.

  • Recycle & reuse. Be economical and environmentally friendly by reusing jam jars. Just check they are undamaged and still have a good seal.

  • Make sure all jars and equipment are really clean. In particular check lids which have been used for savoury products for any odours that could taint the jam.

  • Simmer fruit gently. By cooking fruit gently, before adding sugar, the fruit will soften and release its pectin. Add water for fruits with tough skins.

  • Sugar should be dissolved over a gentle heat to help hold the fruit together and avoid the formation of sugar crystals on the jam.

  • Add a little butter or margarine. By adding approx 20g for each kg of fruit you will help minimise foaming and reduce waste when skimming.

  • Rolling boil. Once the sugar is dissolved, bring the mixture to a true rolling boil (mass of bubbles/raised height in pan) and refrain from stirring.

  • Stir in Certo and bring back to a rolling boil for a short time (as per recipe)

  • Skim the top. After cooking, remove pan from heat and skim surface to remove any foam, using a slotted spoon.

  • Test the set. Check your jam has reached setting point, by spreading a small amount on a cold saucer. It should ‘wrinkle’ to touch after a minute or so.

  • Rest and settle. Jams and marmalades rich in fruit will benefit from standing for 5 minutes before potting, to allow fruit to sink from surface and distribute evenly.

  • Pot it hot. Jams, jellies and preserves should all be ‘hot-filled’, into dry warm jars, at a temperature of 85°C or above. Take great care when doing this.

  • Fill to full. Jars should be filled to within 3mm of the rim, to minimise the quantity of air in the jar, which can contain micro- organisms.

  • Seal each pot as it is filled. Sealing the top of the pot quickly ensures less chance of degradation due to oxygen and airborne micro-organisms.

  • Label and date. Avoid confusion and waste. Shelf life is typically 12 months. After this, flavour will deteriorate but provided there is no mould on the jam it will still be safe to eat.

  • If having used Certo, your jam has not set The jam will have enough pectin, but you may not have reached the critical sugar content to make the jam set. You need to reboil the jam. Do not be tempted to add more Certo. If the fruit was very ripe and lacking in acidity, it may help to add another tablespoon or so of lemon juice. Put the jam into a large pan without adding any water. Heat to the boil, stirring to prevent burning, then boil as fast as possible for a couple of minutes. Stop boiling, and test a small sample on a cold plate. If it is not setting after several minutes, boil the jam for a further two minutes and check again. Once the jam is setting, pot it up again, and seal as usual.

  • If your Jam has not set and you have not yet used Certo The jam may also be short of enough pectin to give a good set. You can add Certo at the rate of ½ bottle for every 3lb / 1.5kg of sugar you have used in making the jam. You may also find it useful to add lemon juice as above if the fruit was very ripe or low in acidity. You will need to boil the jam for long enough to remove the water added in the Certo. Put the jam into a large pan, and heat to the boil, stirring to avoid burning. Stir in the appropriate amount of Certo, and boil as fast as possible for say 5 minutes. Test a small sample on a cold plate for setting. If not setting, boil again for 3 minutes and test again. Continue until you have a definite set, then pot up and seal as usual

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