Sugar For Chilli Jam

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Nigella's Chilli Jam (from NIGELLA CHRISTMAS is made from red chillis, red (bell) peppers and (apple) cider vinegar. Unfortunately none of these ingredients contains pectin, the substance that causes jams and jellies to set. Jam sugar has pectin added which makes the Chilli Jam set. Unfortunately preserving sugar does not have added pectin, it has larger sugar crystals that can make clearer jellies and should be used with fruits that are naturally high in pectin. The Chilli Jam has a soft set, so if you use a mixture of the two sugars then there is the risk that there will not be enough pectin to make the jam set at all.

When making the jam you may also want to check that it has reached setting point after the boiling time, as different sizes of pans can mean that the cooking time varies slightly. You can use a jam or preserving thermometer and boil the jam to 104c (220F). The cold plate test is also a good way to see if the jam has set. Put 2-3 heatproof plates in the freezer before you start making the jam. Once the jam has boiled, remove the pan from the heat, drop a teaspoonful onto a frozen plate and leave for a minute. Then push the blob of cooled jam with your finger. If the surface of the jam wrinkles then it should be set. If you push your finger through the cooled jam and it flows back quickly and looks quite liquid then boil the jam for a further 3 minutes (time from when the jam comes back to full rolling boil) and test again.