Proper ginger beer

Method

Put the ginger, lemons, sugar, cream of tartar and 1.5 litres water in a stockpot or large pan and heat gently, stirring until the sugar has dissolved. Bring to the boil, turn off the heat, then add 3 litres cold water and stir in the yeast. Cover, then leave overnight in a cool place.

Strain into a jug, then pour into large clean plastic bottles. Leave a 5cm gap at the top to accommodate any gas build-up. Screw the lids on tightly and store in a cool place, unscrewing the tops to release the built-up gas every few hours.

The ginger beer will be ready to drink in about 48 hours. Keep chilled and drink within 3 days. Discard any that smells musty or yeasty.