Make a syrup by dissolving the sugar in the water in a large pot over a high heat. Cook the sugar syrup and check with a thermometer that reaches 110˚C.
Add the white peach wedges, the jasmine tea, the lemon juice and zest to the syrup.
Bring to the boil and stir regularly with a spatula. Skim off any impurities that come onto the surface while cooking.
Cook the jam until the thermometer shows 105˚C.
Spoon the cooked jam into jars, seal the lid and place them upside down to cool down.
Notes
The lemon is ascorbic acid (vitamin C) which stops the oxidation of the fruit. The acidic pH of citric acid makes it useful as a preservative. Lemon also contains a natural pectin which helps to jellify the mixture.
Make sure to use very clean glass jars and lids. Soak them in boiling water for a minute and place them upside down on a wire rack.