Before starting the jam recipe, start the boiling water in the canner for the sterilization of the jars. This takes much longer than the jam. Wash jars in hot soapy water rinse and place into the canner before the boil. It's much easier to get them in early. Boil jars for 10 minutes. Leave inside until needed.
Yield: About 5 - 8oz jelly jars
6c Maine Blueberries
Put into a pan that has about double of the capacity of the sugar and blueberries. This is to prevent a spill over when you raise the heat. I like to combine the sugar and berries before turning on the heat.
Heat on med-low and stir until all sugar is dissolved. Then turn up the heat and bring the jam up to 220 degrees. It takes longer than you think.
After reaching 220 remove from heat. You can start filling the 8oz jars that are in the hot water. When I working alone I take out one jar at a time. Fill with 1/4" headspace, wipe the rim, put on lid and screw on band.
Sorry it's blurry.
<<I tried this method for processing the jars. My friend said that until the 70's everyone did this. Using a cloth tile turn the jar upside down and leave it that way for at least 5 minutes or more. I did and three of the five created a vacuum, two did not...I think I might not have waited long enough so I conventionally proceed>>>
If using hot water bath to process. Have the temp at 180 and process for 15 minutes.