(Editor note: This September, the Eat Local Challenge blog will be hosting an international, month-long eat local challenge in association with the Locavores. This particular challenge will have a special focus of preserving, canning, and putting food up for the winter. Stay tuned to this site in the next few days for more information. Meanwhile, this first post from Marc discusses making plum jam at home.)
By Marc
The grounds around my apartment have two plum trees that become heavy with fruit in the mid-summer. The first few years I lived here, I didn't do anything with them except perhaps eat a few, only to rediscover that they are almost all pit and skin. But last year my upstairs neighbor taught me how to make plum jam, so this summer I was sure to spend part of each weekend on a ladder harvesting as many plums as I could, even creating a strange contraption called "the depluminator" to pick fruit growing on high boughs beyond my reach.
Jam or jelly can be a fantastic way to preserve the bounty of local summer fruit. A significant non-local component, however, is often required in the form of large quantities of sugar. Much of the sugar sold here comes from the tropics, often produced by ill-treated workers on ill-treated lands. Sugar beets are another source of white sugar, with California produces
only about 6 percent of the U.S. crop (most comes from Minnesota and
North Dakota). (An episode of the Deconstructing Dinner radio program goes into great detail about sugar, stevia and honey).
In a quest to learn more about fruit and vegetable preserving, I came across a Rodale Press book called "Stocking Up." The recipe called "Plum Honey Preserves" immediately grabbed my attention, as it would allow me to create an all-local plum preserve.
The recipe in the book--which I have posted below--instructs you to manually remove the pit from the plums before cooking the fruit. Although I'm not averse to shortcut-free cooking, there is no way I was going to remove the pits from over 100 grape-sized plums. So I tried a cook-then-strain method, first cooking the plums in a little water until they were soft, then pressing them through a colander, as shown in the photo. The photo also shows a little trick I used to hold the colander in place, and thus press with less mess. I threaded a piece of stainless steel wire through one of the holes in the colander and then wrapped it around the pot handle.
Due to my inexperience, and perhaps too little extraction of pectin during the plum softening and pressing, my jam did not fully set. But it is still delicious, with a combination of sharp, tart plum flavors and a mellow honey background. And it's all from within 100 miles of where I live.
In the recipe below I have not included the details about preparing the jars or processing the filled jars. To learn proper techniques, consult a book on home preserving or one of the page in the University of California Food Safety program's collection of on-line resources on home food preservation.
Plum Honey Preserves
Adapted from Stocking Up, by Carol Hupping and the staff of the Rodale Food Center
Makes enough to fill three to four half-pint jars
Ingredients
2 pounds red or purple plums (but not prune plums), slightly underripe, or a mixture of ripe and underripe
1 cup honey (a variety with mild flavor is recommended)
Method
Use a heavy six- to eight-quart pot made of stainless steel or enamel-coated metal, ideally one that is wide and short to allow faster evaporation of water.
There are at least two ways to prepare the plums: 1) Pit the plums and cut them into large chunks. 2) Cook the whole plums in a small amount of water over medium heat until they are tender, then press them through a sieve or colander, pressing hard to extract as much pulp as possible.
Combine the plum pieces or pulp and the honey in the pot. Bring to a boil over low heat, stirring frequently. When the mixture appears soupy, increase the heat to bring the mixture to a full, rolling boil.
As the mixture boils, stir it slowly. After fifteen to twenty minutes of cooking, the fruit and honey will become translucent and darken slightly. Use one of the classic tests (thermometer, cold plate, the spoon test) to determine when it is time to stop cooking.
Pour into the hot jars, maintaining 1/4 inch headspace, then seal. Process for ten minutes in a boiling-water bath.

