It is best to use cultivars. Their fruits are large, fragrant, highly colored. Of wild blackberries should be selected juicy, ripe and highly colored fruit. Clean blackberries by taking core and wash shower. Place in pan and sprinkle with half the sugar. Leave to stand in a cool 5-6 hours. Gets cooked syrup from the rest of the sugar, water and compartments blackberry juice. Allow to cool a little. Add fruit and gently shake the container to sink into the syrup. Place back on heat and boil until the required density. Scalding is harvested foam. 2-3 minutes before the citric acid was added.