Boil fruit with juice for 5-10 minutes, depending on firmness (increase amount of liquid if cooking time is longer).
Add remaining ingredients and bring to a boil, stirring constantly, blending if necessary, and boil for 4-5 minutes until bubbly.
Make the jelly test.
Immediately pour the pear jam into prepared jars, drizzle a few drops of alcohol over them with the help of a pipette, light and seal immediately.