This recipe can also be found at Kraft Foods using Certo Pectin. Lemon zest optional.
Yield: 9 - 8 oz. jars
5 cups crushed strawberries
7 cups sugar
zest of 1 lemon
juice of half a lemon
1 tsp butter
1 package Certo Pectin (57 gr)
10 – 8 oz. canning jars with lids and rims
(all jam recipes seem to say not to double recipe, make separate batches)
Heat water in a large stockpot or canner. Wash 8 oz. canning jars with warm sudsy water. Rinse thoroughly. *Only clean jars, set lids and rings aside. Put jars into the pot and make sure they are covered with water by 2 inches. Gently boil water. Jars must be sterilized. Do not take them out of the water. Keep canner (stockpot) gently boiling.Heat water in a small sauce pan to a slow simmer. This will be used to warm up the lids. Keep water slowly simmering. Do not put lids in yet!
Rinse and hull strawberries.
Mash 1 cup of strawberries at a time to equal 5 cups. A potato masher works great.
Put strawberries in a large pot and add 1 package of Sure Jell Premium Fruit Pectin(I used Certo) , zest of a lemon, lemon juice and butter ( butter keeps the foam to a minimum). Heat over medium heat stirring constantly. Bring strawberries to a rolling boil
Add sugar all at once. Stirring constantly bring the mixture back to a boil for 1 minute.
Remove from heat.
Put lids (not rims) in the small saucepan and take off heat.
Take 1 jar out of simmering water at a time CAREFULLY. Skim off any foam that has formed on the top of the jam. Ladle jam into jars. Wipe off the rim of the jar with a clean damp paper towel.
Take lid out of hot water with tongs and place on jar. Screw on rims.
Put jars back in canner and process for 10 minutes. Take out of canner and put on a doubled kitchen towel.
As the jars cool, listen for that little"click" of the lids that tells you that they are sealed.
Let cool. Check that each lid has sealed by pressing the center of the lid. If it clicks or you can push the center down, refrigerate or freeze this jar because it has not sealed properly.