This is what I found when looking up what to do if your jelly doesn't set:
Pectin manufacturers and food preservation experts have developed these "fix its" for problem jams and jellies. With any remake project, follow the directions and recook a 250 mL (1 cup) trial portion. If it sets, then proceed to redo the entire batch, keeping in mind the guideline of cooking no more than 2 L (8 cups) at any one time. REMEMBER powdered pectin and liquid pectin are not interchangeable. You must use the same type of pectin that you used in the initial recipe.
* To remake cooked jam or jelly using powdered pectin measure 15 mL (1 tbsp) water and 7 mL (11/2 tsp) powdered pectin for each 250 mL (1 cup) product into a large saucepan. Bring to a boil stirring constantly. Remove from heat and stir in jam or jelly. Add 25 mL (2 tbsp) sugar per 250 mL (1 cup) of jam or jelly being recooked. Return to the heat and bring to a full rolling boil, stirring constantly. Boil rapidly for 30 seconds. Remove from heat, skim off foam, fill hot sterilized jars, seal and process 5 minutes in a boiling water bath.
* To remake cooked jelly or jam using liquid pectin for each 250 mL (1 cup) jelly or jam, measure and combine 45 mL (3 tbsp) sugar, 7 mL (11 /2 tsp) bottled lemon juice and 7 mL ( 11/2 tsp) liquid pectin. Bring jam or jelly to a boil stirring constantly. Add the sugar, lemon juice and pectin combination. Return to full rolling boil, stirring constantly. Boil rapidly one minute. Remove from heat, fill jars and process as per original recipe instructions.
* To remake freezer jam and jelly with liquid pectin, measure jam or jelly in a bowl. Add 45 mL (3 tbsp) sugar and 7 mL (11/2 tsp) lemon juice for each measured 250 mL (1 cup) product. Stir approximately three minutes until sugar is dissolved. Add 7 mL (11/2 tsp) liquid pectin per each 250 mL (1 cup) product. Stir three more minutes until well blended. Pour into freezer containers and cover with tight lids. Let stand in refrigerator until set, then transfer to freezer.
* To remake uncooked jelly or jam with powdered pectin measure jam or jelly to be remade. Work with 2 L (8 cups) at a time. Mix jam or jelly with 25 mL (2 tbsp) sugar for each 250 mL (1 cup) of jam or jelly. Stir well until dissolved about 3 minutes. Measure 15 mL (1 tbsp) water and 7 mL (1/1/2 tsp) powdered pectin for each 250 mL (1 cup) of jelly or jam. Place in a small saucepan over low heat, stirring until powdered pectin is dissolved. Add to the sugar and fruit mixture and stir until blended (about 2 to 3 minutes) pour into clean, sterilized containers. Cover with tight lids. Let stand in the refrigerator until set. Store in the freezer.
* To remake cooked jam or jelly without added pectin, for each 1 L (4 cups) jam or jelly add 25 mL (2 tbsp) bottled lemon juice. Heat to boiling and boil jam or jelly hard 3 to 4 minutes, then test for signs of gelling. Try the sheet test from a cold spoon or remove the kettle from the heat and chill a little in the freezer. If it shows signs of gelling, boil until it tests done. Remove from heat, skim, pour into sterilized jars, seal and process in a boiling water bath the recommended length of time.
- Response by barbb
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