Preparation time: 20 minutes
Cooking time: 40 minutes [approximately]
Makes: 1.75 litres
500g [1 lb] net weight green cooking apples
1kg [2lb] blackberries
454g of sugar to 570ml of liquid
Juice of 1/2 lemon for taste
1. Peel, core and chop the apples. Pick over and wash the blackberries. Remove the stalks from the berries, cut away and discard any damaged or bruised fruit.
2. Place both fruits in a large pan with 125ml [4fl oz] of water. Simmer slowly over a medium heat until soft [approx 20-30 minutes]. Stir often to avoid sticking.
3. Leave to cool, then measure liquid in ml.
4. Add 454g of sugar to every 570ml of liquid and stir, without boiling, for 5 minutes or until all the sugar has dissolved.
5. Bring the mixture to the boil and boil rapidly for around 7-10 minutes stirring often. Stir across the base of the pan to check the jam is not sticking or burning.
6. Test for setting point when the jam looks thick and syrupy [see below]. When set, remove from the heat. Remove any scum from the surface with a large spoon. A knob of butter also helps disperse the remaining scum.
7. Add the lemon juice and stir.
8. Transfer the jam to a heat proof jug [can use a ladle and funnel] and immediately pour into warm sterilised jars, wipe clean and add lids. [See below]
9. Leave to cool. Use within 12 months of making. Refrigerate after opening and use within 6 weeks.
- Try not to cook too much jam in one go. Do not use more than 4lb of fruit in a recipe at a time.
- Make sure your pan is large enough and preferably, is heavy-based. Adding sugar increases the volume. Jam can rise up the pan when boiling.
- Bottle [jars] – check there are no chips or cracks. Wash bottles and lids in a dishwasher or hot soapy water and rinse well. Dry and sterilise the bottles in the oven. Place on a baking tray and leave in an oven [preheated to 120 degrees Centigrade/Gas Mark ½] for 20 minutes or ready to use.
- Successful jams and preserves need an even balance of acid and pectin in the fruit. Sugar and pectin play a part in the final firmness and flavour.
- Sugar – is not simply a sweetener but is a preservative when used in high concentration as it acts to stop the development and growth of micro-organisms. It is also a setting agent and aids the setting process in jams and jellies. Acid in fruit forms a similar function.
- Pectin – is found in the skin, flesh and seeds of most fruits to varying levels. To test, place 2 teaspoons of methylated spirits in a cup, gently add 1 teaspoon of strained fruit mixture and stir gently. It there is enough pectin to set the jelly or jam, clots should form into one large clump. If they form only small clumps you will need to add some lemon juice to the mixture in the pan.
- Cooking times – vary greatly depending on the size of pan used, fruit used, whether it is in season, it water content etc. Therefore it is best to test the setting point sometimes 10 minutes before the time stated in the recipe. Do not rely only on the times given.
- Testing for setting point: Take a large spoon of jam, tilt it and it should fall from the spoon heavily with 3 or 4 drops joining together as they drop. They may form a sheet and be slow to drop. It is ready for bottling. Alternatively you can take a teaspoon of jam, put onto a cold plate [need to put these into a freezer when you begin], return to the freezer for 30seconds or till cooled to room temperature. There should be a skin on top of the jam, which wrinkles if you gently push it with your finger- tip.