It's late summer now and the apples are a fair size and colouring up. It's good practice to thin your apples, enough so the ones you leave can grow to their full potential and the tree isn't too stressed. With the dry summers we had in 2009 and 2010, the trees tended to self-thin, by dropping some of their fruit when conditions got too hard. (Curiously it hasn't happened so much this year even though it's been exceptionally dry all year.) I like to use the thinnings or windfalls for apple jelly, and I recently discovered that our orchard neighbour does too.
Step 1: Wash about 25 apples, then cut into quarters. Cut out any bad sections, but otherwise just put in a stockpot, seeds, peel and all. Apples float, but put in enough water that you would cover them if they didn't, if you see what I mean. Cover, put over medium heat and bring slowly to a gentle boil. Cook for 15-25 minutes until they have exploded and you have a mixture of sloppy pulp and skins.
Step 2: Arrange a muslin cloth in a large bowl and tip the cooked apple in. Gather up the corners and sides of the cloth and tie off the bundle.
Step 3: Take the bundle and the bowl to somewhere you can suspend the bundle over the bowl to drip. I use a ladderbacked chair. Tie the bundle to the chair. You will need an assistant for this, ideally one who has been a boy scout or a sailor, and can tie self-tightening knots while you take the weight of the bundle. Be careful, as the fruit inside the cloth is hot and dripping all the while, so you also have to make sure the bowl stays underneath. If you use the back of a chair like this, to avoid a nasty overbalancing accident, put a large heavy book on the seat. I find the Italian cooking bible The Silver Spoon is perfectly suited to this task. Leave the muslin bundle to drip overnight.
Step 4: Put the liquid in the bowl in the fridge. Sit the muslin bundle in a container and balance a heavy weight on top to press out more liquid. I use a jar of small change. Leave overnight. Don't worry that by pressing you will end up with cloudy jelly.
Step 5: Remove the weight and put the muslin bundle on a plate. Pour the liquid into a measuring jug. Also measure the original liquid in the bowl and combine the two. You will probably have about 2 litres of liquid. At this stage it is liquid pectin, and can be frozen in batches for use in other jams, or you can use it to make apple jelly. Untie the muslin and tip the apple pulp into the compost or put it aside to run through a food mill later (when it can be used as a substitute for fat in low fat biscuits or toasted muesli). Thoroughly rinse the muslin out in very hot water until it is fruit free and dry it. You can iron it if you are concerned it is not sterile prior to its next use.
Step 6: Add sugar in the ratio of 4 parts liquid pectin to 3 parts sugar. Stir well, then leave in the fridge for 2-3 days until the sugar has completely dissolved.
Step 7: Bring to the boil, stirring once to ensure the sugar really is dissolved. Once it is boiling merrily and you can't stop the boiling by stirring you should have reached jam temperature. I find that my thermometre reads a few degrees low, probably because the level of the jam isn't high enough to ensure an accurate reading. Once its gone over 100°C, I give it 5 minutes of the proper rolling boiling (see photo below), then take it off the heat.
If it foams up out of control (see photo below) take it off the heat immediately and allow to cool a little, then bottle.
Step 8: Ladle into a jug then pour into 'sterilised' jars. Put the lids on immediately and tighten. Leave to get completely cold, then label and store in the pantry.