Sterilize the jars with lids (for twisting), wash the pears and cut the tails on both sides.
Cut the pears into quarters and remove the seeds. Place them in a cooking vessel and add water. Cook over low heat for 8-10 minutes, stirring constantly.
Grind the pears with a blender. Add sugar and citric acid, stir. Bring to a boil over moderate heat and cook for 6-7 minutes.
Distribute the hot puree into dry, sterilized jars and close the lids tightly. Wrap in a warm towel and leave to cool. Then store it in a cool, dark place.
Pear puree is suitable for tea drinking, and will also be an excellent addition to porridge, cheesecakes, casseroles, or as a layer for cakes and pies.