Adapted from williams-sonoma.com
For the calcium water:
tsp. calcium powder
lb. fully ripe peaches (see “Perfect Peaches” tip below)
cup lemon juice
cup pure maple syrup
tsp. Pomona's universal pectin
To prepare the calcium water, in a small, clear jar with a lid, combine the calcium powder and the 1/2 cup water. Shake well. You will need 4 tsp. calcium water for this recipe; store the extra in the refrigerator for future use. Wash 4 or 5 half-pint jars, lids and bands. Place the jars in a canner, fill the canner two-thirds full with water and bring to a rolling boil. Boil the jars for 10 minutes to sterilize them. (Add 1 extra minute of sterilizing time for every 1,000 feet above sea level.) Reduce the heat and allow the jars to remain in the hot canner water until ready to use. Place the lids in water in a small saucepan, heat to a low simmer and hold until ready to use. Peel and remove the pits from the peaches, and then mash the peaches in a large bowl. (See “How to Skin a Peach” tip below.) Measure 4 cups of the mashed peaches (save any extra for another use) and pour the measured amount into a saucepan. Using a paring knife, slice the vanilla bean in half lengthwise and scrape out the seeds. Add the vanilla seeds and the bean pod to the peaches, along with the lemon juice and the 4 tsp. calcium water. Mix well. In a separate bowl, combine the maple syrup and pectin. Mix thoroughly and set aside. Bring the peach mixture to a full boil over high heat. Slowly add the pectin-maple syrup mixture, stirring constantly. Continue to stir vigorously for 1 to 2 minutes to dissolve the pectin while the jam returns to a boil. Once the jam returns to a full boil, remove the pan from the heat. Using tongs, carefully remove the vanilla bean pod and discard. To can the jam, remove the jars from the canner and ladle the jam into the hot jars, leaving 1/4 inch of headspace. Remove any trapped air bubbles, wipe the rims with a damp cloth, put on the lids and screw bands, and tighten to fingertip tight. Lower the filled jars into the canner, ensuring the jars are not touching each other and are covered with at least 1 to 2 inches of water. Place the lid on the canner, return to a rolling boil and process for 10 minutes. (Add 1 extra minute of processing time for every 1,000 feet above sea level.) Turn off the heat and allow the canner to sit untouched for 5 minutes, then remove the jars and allow to cool undisturbed for 12 to 24 hours. Confirm that the jars have sealed, then store properly. Makes 4 to 5 half-pint (8-oz.) jars. Tips Perfect Peaches: This recipe requires mashed peaches, so be sure that your peaches are fully ripe and soft enough to mash. If they’re not, however, simply place the peeled, pitted and chopped peaches in a saucepan with 1/2 cup water. Simmer for 5 minutes to soften them and then mash. (There is no need to drain the water after cooking; simply mash the peach mixture as is.) How to Skin a Peach: If you are dealing with a small quantity of fruit, slice off the peach (or nectarine) skins with a paring knife (pitting and quartering the fruit first). However, if you’re doubling the recipe and are working with a lot of fruit, you may want to blanch them to remove the skins instead. Simply drop the peaches or nectarines one at a time into boiling water for 30 to 60 seconds, then remove and immediately immerse in cold water. You should then be able to slip the skins right off.