Strawberry preserves
When strawberries flooded the farmers' markets, I was determined to make them last as long as I could. I diced up strawberries to make jam, and left the fruit whole to make preserves. Since I live so close to a weekly farmers' market, I wanted to preserve the seasons, taking advantage of all the beautiful produce I saw. Come winter, when I crave strawberries (not the bland jumbo strawberries from the store), I can open a jar of homemade jam.
For a few weekends in a row, I went on a jamming spree, buying a lot of strawberries and rhubarb. Not from a family who made jam, I used recipes from
Canning for a New Generation by Liana Krissoff. But after tasting my preserves, someone mentioned to me how "watery" the preserves were. I searched the Internet for other jam recipes until I read about
Eugenia Bone who writes the
Well-Preserved blog for The Denver Post.
I figured out why my first few jams were so thin: 1) I needed more sugar and 2) I needed to bring the fruit and sugar to a hard boil.
Krissoff's recipes have a low-sugar content and call for simmering the fruit until it's supposed to thicken.
That doesn't work. You really need to boil the fruit and sugar together until a candy thermometer reads 220 degrees F and the jam will gel. (If you live at a different altitude than sea level, the
National Center for Home Food Preservation has more information about what temperature you need to boil your jam to.)
Now that I knew how to fix the problem, I made strawberry jam with much better results.
Strawberry Jam
Makes about 3 half-pints
2 pounds strawberries, washed, hulled and diced
3 cups sugar
Zest and juice of 1 lemon
If canning, sterilize jars by putting them on a plate or rack inside an 8-quart or 12-quart pot and filling the pot with cold water to cover the jars. Bring to a boil and heat the jars for at least 10 minutes. Leave them in the water bath until ready to use. Put the lids and rings in a bowl and set aside. Place a small plate in the freezer to test the consistency of the jam later.
Heat strawberries and sugar over low heat in a 5 to 6-quart enameled pot. Stir occasionally until the sugar has melted and the fruit is swimming in its own juice, about 15 minutes. Add zest and juice of 1 lemon. Bring mixture to a hard boil, stirring occasionally. Cook until the berries and their juice have thickened and the temperature on a candy thermometer reads 220 degrees F*, about 30-40 minutes. Skim off any foam. To test the consistency of the jam after 30 minutes, take out the plate from the freezer and place a teaspoon of jam on it. If the jam gels after a minute, it's done. If not, keep cooking the jam until it gels.
If not canning the jam, let the jam come to room temperature, about 4-6 hours, and store in the refrigerator for up to 2 weeks. Otherwise, ladle water from the hot water bath over the lids to soften the rubber seals on them. Ladle the jam into the sterilized jars. Screw the lids on finger-tight and place the jars in the water bath for at least 10 minutes. Pull out the jars, putting them on a towel or trivet. You will hear the lids pop after several minutes, indicating the jars have sealed. (However, if the center of the lids can be pushed up and down, the jars have not sealed and need to be refrigerated.) Once sealed, let the jars come to room temperature and store.
*Note: For every 1,000 feet of altitude above sea level, subtract 2 degrees F from 220 degrees F.
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