Place the raspberries in a large saucepan and add the sugar, water and lime zest, then heat gently stirring until sugar has dissolved.
Continue to cook gently for a few minutes until the raspberries are very soft about 5 minutes.
Remove from the heat and allow to cool for 10 minutes then stir in the lime juice.
Allow to cool completely and then strain the mixture through a fine sieve or coarse sieve lined with muslin. Allow to stand until all the juice has dripped through.
Pour into sterilised bottles. Seal and allow to cool then chill until required
Diluted to taste with still or sparkling water. Serve over ice and decorate with a few extra raspberries if desired.
To steralise the bottles wash in warm hot soapy water and rince well. Place the wet bottle on a tray, heat the oven to 140℃ (120℃fan)/275°F /gas 1 and put the bottle in the oven for about 10 minutes. To steralise the lid place in simmering water for about 5 minutes.Nutrition information is calculated usingan online nutrition database - is approximate and is meant as a guideline only.