Bring boiling water canner, half full with water, to simmer.
Wash jars and screw bands in hot soapy water; rinse with warm water.
(I wash the jar lift and funnel at this time also).
Place lids in separate saucepan, cover with water and simmer.
(Note place lids back to back so they do not slide together like they are packed, this will make it easy to get out later.When they start to simmer turn off burner. This process softens the rubber, getting the best seal possible.).
Chop unpeeled rhubarb finely. Place into 4 qt saucepan with water.
Bring to boil on high heat. Reduce heat to medium, simmer 2 minutes or until rhubarb is tender.
Measure EXACTLY 4 1/2 cups prepared rhubarb in 6-8 quart saucepan, they mean COOKED HERE.
(I measured out 4 1/2 cups Rhubarb and found that when you cooked it of course it cooked down, so this is why I changed the ingredient list to 6 1/2 cups).
Stir in pectin with rhubarb. Cook for 2 minutes at a roiling biol. Add sugar. Add butter to reduce foaming.
Stirring constantly, bring to full rolling boil (a boil that does not stop when stirring) on high heat. Boil exactly 1 minute at a full rolling boil.
Skim off foam, with metal spoon.
Ladle immediately into prepared jars, filling to within 1/8 inch of tops.(I never fill this full, I only fill to shoulder of jar, but this is what Kraft says).
Wipe jar rims and threads clean.Cover with two piece lids. Screw bands tightly.
(I keep a bowl ready to spoon the extra jam, into.).
Place jars in elevated racking canner. Lower into canner.
Water must cover jars by 1-2 inches (more for higher altitude).
Add boiling water if necessary (and ONLY BOILING WATER).
Cover with lid of canner and bring to gentle boil for 10 minutes.
Remove jars. Place upright on towel and cool completely.
After jars cool completely check seal by pressing middles of lids with fingers.
If lid springs back it is not sealed, refrigerate these jars.
Kraft kitchen tips:
After skimming foam add a few drops red food coloring.
Altitude chart: above 1,000 ft, increase processing time as indicated.
1,001 to 3,000 ft Increase processing time by 5 min.,.
3,001 to 6,000 ft increase processing time by 10 min.,.
6,001 to 8,000 ft increase processing time by 15 min.,.
8,001 to 10,000 ft increase processing time by 20 minutes.
Every once in a while, you may find your jam does not set the way you expected. If your efforts resulted in a runny batch, try our remake directions to improve your jam. If your jam still does not set, you can always use it as a glaze or syrup.
Go to Kraftfoods dot com for these instructions.
(NOTE:Sure Jell, Certo, and MCP all have different recipes.).