How to Can Jam at Home
Try as I might, I've never been able to make enough jam in one season to outlast the yearand my kids' appetites. Prepping several batches of all our favorite typesStrawberry, Blueberry, Wild Black Raspberry and Cherryeach year has become a family tradition, almost as much as eating a dollop of home canned jam on everything from vanilla ice cream to Sunday morning wafflesand I'm honestly not sure which is more beloved.
Though we all have our favoritesmy husband prefers Cherry, my daughters like Wild Black Raspberry and Blueberryit's no accident that this post features Strawberry. Not only is it my favorite, it's got deep roots in my childhood, when I would spend summer afternoons picking the plump, red, Michigan berries in the fields behind my Grandparents' farm house. Of course, Strawberries are also the earliest ripening of all the most popular jam fruits, ripe now in many areas of the U.S. and soon to come in most the others. This means you can get started right away.
Basic Strawberry Jam
makes about (8) half pints or (4) pints
- 5 Cups Crushed Strawberries (approx. 5 pounds)
- 1/4 Cup Lemon Juice
- 7 Cups Sugar
- 1 Box Original Fruit Pectin
Before beginning, prepare your jars, lids, canner and measure your sugar into a bowl. Jars simply need to be clean and hot. The canning process is designed to sterilize everything inside your jarsincluding the jars themselvesso you don't need to do this ahead of time. To get them clean and hot, you can run them through a hot rinse cycle on your dishwasher, rest them in a sink filled with boiling water oras I doput them in your canner, cover (and fill) with water and allow them to heat on a separate burner while you work. This preps your canner and jars in one fell swoop. Lids should be placed into a small saucepan with water and simmerednot boileduntil needed. It's also a good idea to get your canning tools close at hand and put out a towel on the counter where you plan to fill and cool your jars of jam.
In a colander, rinse whole berries well. If you've sourced your berries from a local you-pick or ready-picked farm, pay special attention to remove any debris. Once rinsed, hull berries and crush using a potato masher orand this second option is especially recommended if you have kidsyour hands. If you like lots of lumps in your jams you can crush them lightly, leaving some bigger chunks. If you like a smoother jam, crush more liberally. You can't go wrong here.
Once crushed, measure your berries and lemon juice into a six or eight-quart saucepan and mix well. Gradually stir in the fruit pectin and, continuing to stir constantly, bring the entire mixture to a rolling boil that cannot be stirred down over high heat. Once boiling, add the sugar all at once and bring the mixture back to a rolling boil that cannot be stirred down. Boil for one full minute before removing from heat. Skim any foam off the top and ladle into your hot jars, leaving 1/4 inch of headspace between the top of the jam and the rim of the jar.
When jars are filled, remove the lids from their simmering bath and, working quickly, dry with a clean towel. Place them on top of your jars, being sure to wipe any jam residue from the rims of the jars as you go. Add your rings, screwing them down to "fingertip tight," or just snug. Carefully place the jars in your canner, being sure to "balance" their placement around the canner, not concentrating the jars on any one side. Place the lid on the canner and bring to a rolling boil. Boil for ten minutes. Turn off the heat, remove the lid and let the jars sit for five minutes before removing from the canner and allowing to cool on the towel-covered counter you prepared earlier.
As they cooland sometimes even as you remove them from the canneryour lids will "ping." This is a sign they're sealing and your canning has been a success. As hard as it may be to wait, it's not recommended that you check your seals until the jars have had time to fully cool. Once cool, you can press the center of each lid with your finger. If the lid does not depress under the pressurethink of a Snapple lidyou've got a seal.
Homemade jams can be kept in a cool, dark pantry as long as the seal has not been compromised, but should be consumed within a year or two for best quality.
A naturally-occuring substance found in most fruits, pectin is what makes jams, jellies and preserves thick. When heated, pectin interacts with both the natural sugars in the fruit and any sugar you've added to your jam and jelly recipes, thickening the final product. Though the recipe in this post uses powdered pectinwhich can be purchased in single serving boxes or bulk containerspectin is also available for purchase in liquid form, andif you're feeling adventurousyou can make your own. Apple peels, such as those left over from a big batch of applesauce, are one of the best commonly available sources. Homemade, liquid and bulk pectin can be tricky though, so if you're just starting out you might want to stick with a pre-measured, single-serving box of the powdered stuff.
Looking for more canning tips, tricks and recipes? Our Practice of Preserving series will run throughout the year. From Home Canning Safety to putting by meat, we'll have a new feature each month to help you make the most of 2012's bounty!