To Cook Jelly: Bring the apple juice back to the heat with the sugar (please refer to my notes below for apple infusion sugar ratio).
07Bring to a rolling boil and decrease the heat a bit, but make sure it still cooks.
08Cook down the jelly until you have reached the setting temperature with the thermometer. Finally, check if the jelly has set by adding a drop of hot jelly on an ice-cold plate which you kept previously in the freezer. If it's running, it needs to cook further down. Repeat the test or use check if thermometer until it's set.
09Once the jelly is set, get your sterilized clean jam jars and fill the jars up to the rim with the jelly.
10Close the jar tight with the lid and turn it quickly upside down. This will create a vacuum, which allows the jelly to last longer.
11Once the jars are not hot anymore, turn the jars back up and stick a label on them so that you know when you made them. Store in a cool and dry place. Keep in the fridge cooled after unsealing your jelly.