Nectarine Jam - cooking recipe

Ingredients

4 cups peeled pitted crushed ripe yellow nectarines
1/4 cup strained fresh lemon juice
7 1/2 cups sugar
1/2 teaspoon unsalted butter
1 (3 ounce) package liquid pectin

Preparation

In an 8-quart pan, combine the nectarines and lemon juice; stir in about half of the sugar; cover the pan and let stand for 20 minutes.
Remove pan cover, stir in the remaining sugar and the butter.
Over med-low heat, stirring constantly, heat the mixture until the sugar is completely dissolved.
Increase heat to med-high and bring mixture to a full rolling boil, stirring constantly.
Remove the pan from the heat and skim off the foam.
Return the pan to the heat and bring to a full rolling boil; stir in the pectin.
Return mixture to a full rolling boil, stirring constantly; boil, stirring constantly, for 1 minute.
Remove pan from heat; skim off any foam.
To prevent jam from separating in the jars, let jam cool for 5 minutes before filling the jars; gently stir jam every minute or so to distribute the fruit.
Ladle the hot jam into the hot jars, leaving 1/4 inch head space.
Wipe jar rims and threads with a clean, damp cloth.
Cover with hot lids and apply screw rings.
Process half-pint jars in a 200\u00b0 water bath for 10 minutes; pint jars for 15 minutes.