1. Pick non-fibrous, unblemished, firm green mangoes.
2. Get your inspected canning equipment ready. Use soap and warm water to wash the canning jars, ring bands, and lids per the manufacturer’s instructions. Rinse them with warm water. Keep the rings and jars in hot water for hot-packed mangoes.
3. Get your boiling water bath canner ready. Load it with a canning rack and fill it halfway with clean water. Heat the water to a simmer and maintain it at 180°F for hot-packing.
4. Wear plastic gloves to avoid skin irritation, and then wash the mangoes under cool running water to remove bugs, dirt, and pesticides.
5. Using a sharp knife, peel and slice the mangoes lengthwise. Remove the pits and discard them.
6. Make a light or medium syrup, depending on your preference for added sugar. You’ll need 5¾ cups water and 1½ cups sugar for light syrup or 5¼ cups water and 2¼ cups sugar for medium syrup for the 9-pints or 4-quarts load.
7. Pour the water and sugar into a large pot and heat them until the mixture boils. Stir frequently to dissolve the sugar.
8. Place the mango slices in the hot syrup and bring the syrup back to a boil. Boil the fruit for 2 minutes.
9. Fill dry pint or quart hot jars with the hot mangoes and syrup, leaving ½-inch headspace.
10. Use a wooden or plastic utensil to remove air bubbles from each jar.
11. Wipe the jar rims clean using a paper towel dipped in warm water.
12. Add the canning lids to the jars and apply the ring bands on the jars until finger-tight. Load them into the water bath canner without turning or tilting, using a jar lifter. Check that the jar tops are submerged 1-2 inches in the water.
13. Heat the canner to bring the water to a rolling boil before covering it with the lid. Process the jars per altitude and jar size:

Water Bath Canner Processing Time

• 0 – 1,000ft: 15 minutes for pints; 20 minutes for quarts
• 1,001 – 3,000ftft: 20 minutes for pints; 25 minutes for quarts
• 3,001 – 6,000: 20 minutes for pints; 30 minutes for quarts
• Above 6,001ft: 25 minutes for pints; 35 minutes for quarts

Post Processing

1. Once the processing time is over, remove the canner from the heat. Open the lid for steam to escape. After 5 minutes, use canning tongs to remove each jar without turning or tilting it. Place the jars upright on a raised surface covered with warm kitchen towels.
2. Allow the jars to cool for 12-24 hours, undisturbed. Do not retighten the lids.
3. Unfasten the ring bands to test the jar seals. Press the seals down to ensure a firm seal. If the lids flex, they are not sealed. Cover unsealed jars with new lids and clean bands and reprocess them within 24 hours.
4. Rinse, dry, and label properly sealed jars in a cool, well-ventilated, dry, dark place.