When you visit your friend who has a fabulous garden full of fruit, vegetables and herbs, and she gives you more rhubarb than you know what to do with, you make jam. Rhubarb is a perennial plant (Polygonaceae) that produces red and green stalks (the part we eat) in the spring. I didn’t know this until last week, but rhubarb can be red or green depending on the variety of the plant, and in this case, the variety I used to make jam is called “pink speckled green rhubarb”.
Both methods do require the use of pectin, which is a naturally occurring starch found in fruits and vegetables. It’s activated by sugar and acid, and gives your jams and jellies the set “gelled” texture we expect when we open a jar of jam. Because pectin is activated by sugar, it’s important to stick to the recipe and not reduce the amount of sugar, even if it seems like a lot. There are recipes that use a low-sugar pectin (the Sure-Jell brand comes in a pink box) that allow you to use less sugar, which is a nice option. Another alternative it to make jam without the use of pectin. This works well if your fruit has a naturally high amount of pectin, such as apples, quince and citrus.
Remove your jars from the packaging and wash them with soap and water. Place the jars on a towel- or paper towel-lined sheet tray and slide the tray into a 225° oven until ready to use. Keeping the jars in a warm oven will help sterilize them.
You can reuse canning jars as often as you like, but I always use new lids and rings when canning. The lids and rings can easily rust or get warped, which will prevent them from creating that all-important air tight seal. To prepare my lids and rings, I first prepare my hot water bath. Place a rack in the bottom of a large pot (a deep pasta pot or stock pot works well, or use a pot specifically for canning) and fill it half way with water. Bring the water to a boil, and reduce to a simmer as to not evaporate too much water. Place the lids and rings in the simmering water. This does two things: it sterilizes the lids and rings, and makes them more mailable which creates a better seal. I used tongs to remove them when ready.
In a large pot, measure together the strawberries, rhubarb, pectin, sugar, lemon juice and salt. Stir well and set over medium heat. The mixture will look very dry at first, but as the sugar dissolves and the fruit starts to release its juices, it will become very soupy looking. Don’t worry! Once your jam is done and it cools, the pectin will do its job and your jam will be a beautiful consistency.
I like my jam to have a smooth texture but with some pieces of fruit here and there. In order to achieve this texture, you have two options. The first option is to use a potato masher to mash up some of the fruit (it’s totally up to you how far you want to take it). The second option, which is what I did, was to use an immersion blender to puree some of the fruit but leave some pieces intact throughout for the perfect balance.
Remove your jars from the oven and remove your lids and rings from the simmering water, placing them on the sheet tray with the jars. It’s important to keep the jar threads as clean as possible to get that air tight seal, so I always use a canning funnel during this step. Otherwise just use a ladle, and wipe the threads if any jam drips on them. Fill the jars, leaving 1/2-inch of headroom at the top. Don’t forget to wipe the threads if they need it. Place the lids on top followed by the rings, and screw them on tight.
Using a canning jar lifter (I highly recommend this inexpensive tool!) or tongs, gently lower your jars into the simmering water, making sure the water is covering the jars by 1 to 2 inches, adding more water if necessary. Bring the water to a boil, and only after the water is boiling, start your timer. For the jam, it’s 10 minutes.
Using that super handy canning jar lifter again, remove the jars from the boiling water and return them to the sheet tray. You’ll know the jars have sealed when the lids are concave; sometimes you’ll hear them ping or pop once they seal, which could take several hours so be patient. If 12 hours has passed, and if any of the flat lids are not concave, place the jars in the fridge. Otherwise, you can store them in your pantry or give them to family or friends!
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Yield: Makes 7 half-pint jars, plus a bit extra (see note, below)
Active time: 55 minutes
Start to finish: 4 hours
4 cups sliced strawberries
4 cups rhubarb, cut into large dice
1 package Sure-Jell fruit pectin
5 cups granulated sugar
1/3 cup lemon juice
Pinch of salt
Note:
I had 7 full half-pint jars plus an extra 1/4 cup of jam. I poured this extra bit of jam into a jar and place it in my fridge. Once cool, I put it on a toasted English muffin!