Grate the lemons lightly after having washed them well and cut a small piece of the top and the bottom.
Score the peel of each lemon vertically and remove them carefully so that they don't break.
Roll them into small rolls and secure each one with a toothpick.
Place them in a bowl with cold water and leave them for a day and a night, until they are no longer bitter.
Then, discard that water and boil them over low heat until tender.
Remove the toothpicks and add the sugar, boiling until the syrup thickens.
Remove from heat and set it aside for 24 hours.
The next day, if the syrup hasn't thickened boil once more. Otherwise, place it briefly over heat, add the glucose syrup and the juice and after it has boiled for a couple of minutes store in sterilized jars.
