Ingredients: 1 kg blueberries, 450 gr sugar, 1 cinnamon stick (approx. 10 cm; optional), 4 cloves (optional).
Servings: 1 jar of 450 ml + 1 jar of 250 ml + 1 jar of 200 ml
Preparation
Cover the blueberries with sugar and leave to macerate for 1 hour.
Bring to a boil over low heat at first, until the blueberries release their juice and begin to boil. It takes about 15 minutes. When the whole mixture starts to boil, leave it on the heat for another 1 minute.
Strain the blueberries from the released juice. Leave them to drain for 10 minutes to collect as much juice as possible.
Put the strained juice back on the heat to boil, together with the cinnamon and cloves. Boil for 20 minutes, cleaning the thick foam that forms on top.
Put the blueberries in the boiled syrup. Let it boil for another 8 minutes from the moment it starts to bubble.
Put the hot blueberry jam in the hot sterilized jars, wipe the mouth of the jar if it has become dirty, put the lids on and tighten them well. Turn the jars upside down (to stand on the lid) and leave like this for 10 min. to create a vacuum. Put the still hot jars under a blanket and let them cool like this overnight (dry feather bed).
Store in a cool place, in the cellar or pantry.
Done!