If you are canning peaches, sterilize 2 one-quart jars and lids in boiling water and set them aside on a clean surface. Do not discard the water as you will use it for canning. Turn off the heat. If making refrigerator pickled peaches, the jars and the lids need to be clean but don't need to be sterilized.
Bring a large pot of water to a boil. Prepare a bowl of ice water.
Blanch the peaches in the boiling water for 1-2 minutes, then dunk them in the ice water to cool down.
Next, peel the peaches. The peels should come right off. If not, use a peeler with a serrated swivel blade to remove them.
Cut the peaches in half if they are too large to fit in the jar.
Combine the vinegar, water, sugar, cinnamon, cloves, lemon zest, and peppercorns in a non-reactive saucepan. Bring the mixture to a boil over medium-high heat, stirring until the sugar dissolves. Decrease the heat to low and simmer for 10 minutes.
Poach 3 or 4 peaches at a time in the syrup for 2 minutes. Using a slotted spoon, transfer the peaches to the jars.
Fill the jars with the hot syrup, leaving 1/2-inch headspace. Distribute the cinnamon sticks, cloves, and lemon peels among the jars.
Refrigerator Pickled Peaches
Cover the jars with tight lids and let them cool to room temperature.
Transfer the jars to the refrigerator and store for up to 3 months, possibly longer.
Canned Pickled Peaches
Wipe the rims with slightly damp paper towels or a clean kitchen towel, set the lids on the mouths of the jars, and screw on the rings finger-tight.
Using a jar lifter, gently lower the jars into the pot with the hot (not boiling) water. Make sure that the water covers the jars an inch above the lids. Bring the water to a boil and process the jars for 30 minutes at 1,001-3,000 feet above sea level, 35 minutes at 3,001 - 6,000 feet, and 40 minutes above 6,000 feet. Turn off the heat and leave the jars in the water for 1-2 minutes.
Using a jar lifter, carefully transfer the jars from the pot to a baking sheet lined with paper towels and let them at room temperature for at least 6 hours. Check the seals, label, and store the sealed peaches for up to a year in a cool, dry place. Once open, store in the refrigerator for up to 3 months.
The calories are calculated per single peach with its share of pickling brine. Calories will be much lower without the pickling brine, but calculating them is not easy.