Combine the ingredients: In a large jar or pitcher, squeeze in the juice of all the lemons and add this juice, the sugar, and water. Stir until the sugar is fully dissolved.

Add the lemon peels: Add the juiced lemon peels to the mixture. The natural yeast on the lemon skins will help kickstart the fermentation process.

Close the lid or cover the jar: Close the lid on the jar or cover the jar loosely with a cheesecloth, paper towel, or coffee filter. This allows air to circulate while keeping out dust and debris.

Ferment at room temperature: Let the mixture ferment at room temperature (around 21-24°C) for 3 days, stirring occasionally. You'll start to see small bubbles forming, indicating the fermentation is taking place.

Sieve to remove the peels: Sieve the lemons and pips and strain the liquid. Use a funnel to transfer the lemonade to 2 x 500ml bottles or small jars with lis and close the lid and leave to ferment for 3 days at room temperature. This will help to build up for carbonation.

Burp the lemonade each day: natural carbonation will start to build up so you will have to open the lid to release the pressure and just close. Repeat this each day for the 3 days.

Refrigerate to stop fermentation: Once the lemonade is nice and fizzy transfer to the fridge to stop fermentation

Enjoy your fermented lemonade: Enjoy your homemade fermented lemonade! It will keep in the fridge for 1-2 weeks.

Make sure to use organic, unwaxed lemons so you get the full benefit of the natural yeast on the skins.

The longer you ferment, the more sour and carbonated it will become.