Blackberry Jam

Preparation

1. Prepare some sterilized jars and lids.
2. If you are making only a few jars, you can choose to create a vacuum seal by turning them upside down once filled.
3. Place the blackberries in a colander and rinse them under cold running water.
4. Let them drain and weigh them so that you can calculate the amount of sugar.
5. Weigh the sugar, which should be half the weight of the blackberries, and set aside about 50 g to mix with the pectin.
6. Put the blackberries in the saucepan in which you will later cook the jam and add the sugar, minus the reserved 50 g.
7. Add the water and the juice of one lemon, and stir.
8. Leave to macerate until the next day or, at minimum, from morning to evening.

Cooking and refining

1. Once macerated, place the saucepan over low heat.
2. When it comes to a boil, cook over moderate heat for 7 or 8 minutes, stirring throughout.
3. Use an immersion blender to make the mixture as smooth as possible.
4. To remove the seeds, pass the mixture through a chinois strainer and pour it into a clean bowl; depending on the quantity, do this in several batches.
5. Using a pestle, sieve the blackberry pulp with some force and recover any pulp stuck underneath the strainer by running a knife across it.
6. Return the mixture to the saucepan.
7. When it comes back to a boil, cook over moderate heat for another 5 or 6 minutes, stirring throughout.
8. From this point, monitor the temperature until it reaches at least 102 ºC; at sea level, the text also indicates 104 ºC-105 ºC as the theoretical concentration point of 32-34 degrees Baumé, and at roughly 1,500 m altitude it gives 100 ºC as a reference.
9. Add the pectin mixed with the 50 g of sugar, stirring throughout.
10. Let it boil for another 4 minutes so that the pectin is fully incorporated.
11. Turn off the heat.
12. Skim the jam.

Jarring

1. Fill the jars with the jam while very hot.
2. If you wish to follow the procedure of turning the jars over, fill them as much as possible so as not to leave space for air.
3. To turn the jars over, the jam must be at a minimum of 85 ºC; the text indicates that this procedure is not advisable if there are many jars.
4. Seal each jar as you fill it and turn it upside down.
5. Label the jars with the contents and the preparation date.

Blackberry preserve

Another way to make it according to the Borda Raubert restaurant (La Massana, Andorra).

1. Mix 1 kg of blackberries with 1 kg of sugar and leave to macerate for 12 hours.
2. Pour the contents into a saucepan and add the juice of 1 lemon.
3. Let it boil for 5 minutes.
4. Strain the preparation and set aside the blackberries.
5. Return the liquid to the heat and let it boil for 5 minutes.
6. Add the blackberries back and boil everything together for 5 minutes.
7. Strain the preparation again and set aside the blackberries.
8. Return the liquid to the heat and let it boil for 5 minutes.
9. Add the blackberries back and let it boil for 5 minutes.
10. Skim the preserve.
11. Fill the jars.