Kirsten's blood orange jam

As a follow on this orange jam I decided to make a blood orange version using the same recipe. As I noticed, that the orange jam did not have a gelled texture, I did after some guidance decided to add in some citric acid. And this really do the trick, so my blood orange jam got a gelled texture. I have previously made this blood orange jam.

It takes some time to make this jam, as the orange pieces have to soak cold in water for 24 hours, before it turned into jam.

I will be selling some of the jam jars at work to my colleagues, as I cannot eat 6-8 glasses of jam within reasonable time. And as usual I will donated the money to charity. From sale of various jams in January - May (orange jam & lemon jam) it was possible to donate 110 DKK to Din NødhjælpJulemærkehjemmene.

Kirsten's blood orange jam: 8-10 glasses.

• 6 blood oranges with thin peel
• 1 l water
• 1 teaspoon white wine vinegar - optional
• 1 kg sugar
• 1 teaspoon citric acid
• potassium sorbate - optional

1. Wash the blood orange thoroughly.
2. Do the cutting of the blood oranges on a chopping board, so all the orange juice can be collected and used in the jam mixture.
3. Cut the blood oranges into smaller boat shapes. Afterwards slice the blood oranges "boats" into thin slices. Use a shape knife for all this cutting.
4. Remove the blood orange seeds during the coating process, as they will give more bitterness in the final jam.
5. Blood orange slices and lemon juice in added into a medium-large mixing bowl. Pour the water into the lemon mixture.
6. Store the blood orange mixture cold in the refrigerator for 24 hours.
7. Pour the blood orange mixture into a large cooking pot. Add in citric acid to the mixture.  
8. Let the blood orange mixture simmer gentle for 1 hour without the lid on the cooking pot.
9. Prepare the jam jars by filling them up with the boiling water.
10. If the blood orange slices appear too thick, you could consider to blend the orange mixture, before the addition of the sugar.
11. After 1 hours boiling add in the sugar.
12. Bring the blood orange jam to a rolling boil and boil hard until the setting point is reached. Stir the jam frequently.
13. Test of set after 4-5 minutes using the flake test.
14. When the setting point is reached, remove the pan from the heat and leave it to stand for approx.  5 minutes. As the jam settles, push any scums from the surface of the pan to the side and remove it with a metal spoon. The purpose for the waiting step is well to build viscosity in jam, so the fruit pieces will be trapped inside the jam inside of be going to the top of jam.
15. Gently stir the jam after the resting time and pour it into the prepared glasses, fill the glasses up to the brim. Remove any scum for the surface of the jam using a tea spoon. Close the glass with a lid.
16. Leave the glass upright and disturbed to cool and set.
17. Store at ambient temperature.