Blueberry Pie Filling

Ingredients

Instructions

1. 1Wash 7 quart or 14 pint canning jars in hot soapy water or the dishwasher, keep them hot, and simmer new lids in hot water per manufacturer instructions.
2. 2Rinse the blueberries well and pick out any stems or soft berries; if using frozen berries, thaw them fully and drain off the excess liquid.
3. 3In a very large pot, whisk together the sugar, Clear Jel, and cinnamon if using until no lumps remain, then whisk in the cold water and bottled lemon juice until smooth.
4. 4This recipe requires Clear Jel rather than regular cornstarch or flour, because ordinary starches thin out and become unreliable under the extended high heat of boiling-water processing, risking uneven heating in the center of the jar; Clear Jel is a modified starch engineered to stay stable through that heat.
5. 5Cook the sugar-Clear Jel mixture over medium-high heat, stirring constantly, until it comes to a full boil and turns thick and glossy, then gently fold in the blueberries and return the mixture to a boil for 1 minute, stirring carefully to avoid crushing the berries.
6. 6Ladle the hot filling into hot jars, leaving 1 inch of headspace.
7. 7Remove air bubbles with a nonmetallic spatula, add more filling if needed to keep 1 inch headspace, wipe the rims clean, center the lids, and screw the bands fingertip-tight.
8. 8Process in a boiling-water canner with jars covered by at least 1 to 2 inches of water, timing from a full rolling boil, for 30 minutes for both pints and quarts, adding 5 minutes at 1,001–3,000 feet, 10 minutes at 3,001–6,000 feet, 15 minutes at 6,001–8,000 feet, or 20 minutes above 8,000 feet.
9. 9Turn off the heat, wait 5 minutes, then remove jars to a towel-lined counter and cool undisturbed for 12 to 24 hours.
10. 10Check seals by pressing the lid centers, remove bands, wipe jars, and label with contents and date; store in a cool, dark place up to 1 year and refrigerate after opening, using within about 1 week.
11. 11Never substitute regular cornstarch or flour for the Clear Jel and do not alter the sugar or lemon juice ratios, since this exact combination has been tested safe for boiling-water canned pie filling.