Start to Finish: 26 hours
Difficulty Level: Intermediate
Mulberries resemble blackberries in appearance and flavor, and jam recipes for both are similar. If you have made jams, jellies, cobblers or pies with either type of berry, incorporate similar spices or flavorings into your mulberry jam. This recipe yields enough citrus-and-spice-seasoned jam to fill six 1/2-pint canning jars.
- 9 cups whole mulberries
- 4 cups granulated sugar
- 1/4 cup lemon juice
- 1/2 teaspoon lemon or orange zest, optional
- 2 teaspoons cinnamon, optional
- 1 teaspoon nutmeg, optional
- One 3-ounce pouch liquid pectin
Cook the Jam
Rinse the mulberries, discarding the stems and damaged berries.
Set a large metal-mesh strainer over a bowl large enough to hold all of the mulberries. Add some of the berries into the strainer. Press them against the metal mesh with a spatula or wooden spoon. Repeat the process until you force all of the mulberries through the strainer. Discard the stems or tough mulberry cores that did not go through the metal mesh.
Pour the bowl of mulberry pulp into a large stainless steel or enameled cast iron pot. Stainless steel and enameled cast iron are non-reactive, which means they won't react to the acidity in the jam. Other types of pots can discolor, alter the flavor of the jam or facilitate another type chemical reaction that makes the jam unsafe to eat.
Stir sugar into the mulberry pulp. Bring the mixture to a simmer over medium heat.
Pour lemon juice into the pot. Lemon juice helps preserve the jam and balances the flavor.
Add lemon or orange zest, cinnamon and nutmeg, if desired. Stir the ingredients. Bring the jam to a boil over medium-high heat, stirring constantly to prevent the jam from boiling over or scorching.
Watch for the jam to start thickening naturally. Stir the pectin into the jam. Continue to boil it for at least 10 minutes. The pectin must boil with sugar before it will activate.
Dip a wooden spoon into the pot, coating about 1/2 inch of the spoon with a light layer of jam. Set the spoon over a sink and allow the jam to cool and drip. It should fall from the spoon in a single sheet --not in numerous drips.
Remove the pot from the heat if the jam is close to the desired consistency. Continue boiling the mixture for several more minutes if it needs to be thicker.
Fill and Process the Jars of Jam
Wear oven mitts to avoid burning your hands while you transfer the jam and handle the hot glass jars. Set a funnel on top of a sterilized canning jar, and pour hot jam into the jar. Leave 1/4 inch of head space between the top of the jam and the rim of the jar. Transfer the funnel to an empty jar and repeat the filling process.
Scoop the jam into the funnel with a stainless steel ladle if you are uncomfortable pouring it directly out of the pot.
Wipe the rims of the jars with a damp paper towel to remove traces of jam, which could prevent the jars from sealing properly.
Cover each jar with a canning lid, gasket-side down. Secure each lid with a ring band. Tighten the band naturally but not excessively.
Fill a boiling-water canner with water and heat it according to the manufacturer’s instructions. Transfer the jars into the canner with a jar lifter to avoid breaking the glass. Hold the jars upright to avoid shifting the jam and compromising the jars' seals.
Process the jarred jam according to your altitude.
- Process the jars for 10 minutes at altitudes of 1,000 feet or lower.
- Process the jars for 15 minutes at altitudes from 1,001 to 6,000 feet.
- Process the jars for 20 minutes at altitudes above 6,000 feet.
Turn off the heat source, then remove the canner’s lid. Allow the canner to cool with the jars inside it for five to 10 minutes.
Cover a flat, stable surface near the stove, such as a counter top, with a towel. Choose a surface away from cool drafts -- cold air could cause hot glass to crack. Remove the processed jars from the canner with the jar lifter, placing them upright on the towel-covered surface.
Allow the jars to cool for 24 hours. They should vacuum-seal, and the jam should set during the cooling period. Do not handle the jars or press on the metal lids until the cooling period ends.
Evaluate each cooled jar to assess its seal. Remove the ring and lid of any jar that did not seal properly to inspect the pieces for defects. Reprocess the jar for the recommended time.
Store canned mulberry jam in a dark, dry place between 50 and 70 degrees Fahrenheit. Use the jam within one year.
Stain Prevention, Substitutions and Jar Sterilization
Mulberries temporarily stain skin and may permanently stain fabric, kitchen surfaces and cooking tools. Wear thin gloves, such as latex gloves, to avoid staining your hands. Wear clothes you don’t mind staining. Select cooking tools that are stain-resistant, such as a glass bowl and stainless steel strainer. Protect your kitchen counter as needed.
Nine cups of mulberries should yield about 6 cups of pulp if you discard stems and tough pieces of mulberry core, which some berries may have.
You can substitute another type of berry, such as blackberry, raspberry or blueberry, for some of the recommended volume of mulberry.
Substitute artificial sweetener for the sugar or reduce the sweetness altogether, if desired. Use a low-sugar pectin product if you use artificial sweeteners or reduce the volume of sugar. Pectin needs sugar to activate. Manufacturers add calcium to low-sugar pectin products to activate the pectin in the absence of granulated sugar.
Substitute 2 tablespoons of powdered pectin for a 3-ounce packet of liquid pectin in a sugar-sweetened jam, if desired.
Sterilize canning jars by boiling them in water before filling or washing them alone in a dishwasher. Leave the jars in the pot of water or dishwasher until you are ready to fill them. You should use fresh canning lids to ensure that the gaskets are in optimal condition. You can reuse ring bands.
Hot sugar can cause severe burns if it comes in contact with your skin. Wear a long-sleeved top to protect your forearms and oven mitts to protect your hands. Do not taste test the jam. Hold your skin under cool running water if burns occur. Do not apply ice, which can further damage burned skin.