Add the peaches in batches to a large pot of boiling water and cook for 2 minutes to blanch. Peel and stone the peaches, transfer to a large saucepan, and mash with a potato masher.
Stir in the lemon juice, cinnamon and allspice. Bring to the boil over high heat. Add the sugar all at once, stirring constantly. Return to the rolling boil and cook for 5 minutes or until slightly thickened. Skim off the foam.
Ladle the conserve into containers rinsed in boiling water; fill to within 1 cm of the top. Cover with tight lids and let stand at room temperature overnight. Store in the refrigerator for up to 3 weeks.
Did you know?
Peaches and nectarines are not only sweeter, softer and more fragrant when they're fully ripe, they also contain more vitamin C. These closely related tree fruits are good sources of beta-carotene, vitamin C, niacin and potassium. They also supply some fibre and, gram for gram, contain more potassium than a navel orange.