IMG_6181When making jam there are rules. And rules is rules when it comes to jam:

  1. Prepare everything in advance. Jam making happens fast and good jam is all in the preparation.
  2. Dont drink and make jam! unless you want to visit the burns unit – hot sugar is dangerous.
  3. Use your best heavy bottomed pan BUT you must allow enough space for the jam to foam up and heaven forbid boil over. The jam ingredients should only half fill the pan
  4. Make jam in small quantities. Its what my Nana taught me and she was right. (there is in fact a scientific reason for this to do with boiling, surface area and so forth)
  5. Bacteria love jam.  You must be scrupulously clean and sterilise stuff.  Wash all jars and equipment for stirring/skimming/jarring in a solution of bicarbonate of soda
  6. Jam is all about setting and setting is all about pectin. This chemical reaction takes place at 104C. Fruits vary in pectin levels. Ripeness affects pectin too. I test for setting by placing jam on a saucer placed in the freezer. when it doesn’t run when vertical or “wrinkles” when pushed it is set. This is the one time in life when wrinkles are a good thing. If I am in doubt I use a sugar thermometer. To be sure I take my jam to between 108-110C.
  7. I increase pectin levels by making apple juice and apple puree from under ripe apples and adding this to jams. That way I dont need to add any extra pectin except when making no added sugar jam
  8. Pour jam into clean jars heated to 100C –  I do use a proper stainless steel jam filler but a ladle is fine if you have good hand to eye co-ordination (I dont). If you have a super duper dishwasher and are well timed you can set it at its hottest setting and wizz your too hot to handle jars out of the dishwasher straight to be filled.
  9. Fill to the shoulders of the jar, screw the cap on fast, invert and let the hotter than hell jam sterilise that air gap and kill off any bacteria except if you are American. If you are American you need to then water bath the jams just to be sure. ie put them in a big pan of water and boil ’em up for 20 minutes or a water bath.
  10. If I am making a particularly low sugar jam I water bath it too. Just to be extra sure.
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