Place the sugar and water in a glass bowl and stir until the sugar has dissolved. Place the pineapple peel in a litre glass jar and cover with the liquid. Cover the top with cheesecloth to keep the fruit flies at bay, and leave to ferment at room temperature in a warm draught-free spot.

When the liquid begins darkening, strain out the peel and toss onto your compost heap. It should darken after about a week but if it doesn’t, leave the peel for a little longer until it does. Ferment the liquid for 2–3 weeks longer, agitating it periodically.