Makes four balls of mozzarella, about 200g.

Ingredients:-

• 1 tsp citric acid
• 2 litres whole organic milk, raw or unhomogenised
• ¼ tsp rennet
• 2 tbsp salt

Method:-

• Dissolve the citric acid in 60ml of water – boil the kettle and let the water cool down to just warm, as this will help the crystals dissolve. Pour the milk into a large, non-reactive saucepan and heat gently just to take the chill of the fridge off it – you need it at about 13C. Add the citric acid, and heat to 30C, stirring gently – it will start to curdle.
• Dilute the rennet in a tablespoon of boiled, cooled water and add it immediately to the milk. Warm gently to 38-39C, stirring from time to time – it will begin to separate. Remove from the heat and leave for about 15 minutes, to let the curd set and separate from the whey even more.
• Carefully scoop the curds out of the pan with a slotted spoon and place them in a sieve – leave the hot whey in the pan. Press the curds gently to remove some of the whey – but be careful: you want them to be dripping a little, and if you remove too much the mozzarella will be tough. Add the salt to the whey in the pan and heat to 80C.
• Put the curds on a chopping board and cut them into four 2cm-thick slices. Have a bowl of iced water ready. One at a time, dip the curds into the hot whey for a minute or so, until they begin to soften and stretch. Remove a piece of curd from the whey with a slotted spoon, dip your hands in the iced water (the cheese will be quite hot) and gently stretch out the cheese, folding it back on itself and working it just until it's stretchy, shiny and smooth. Don't be tempted to overwork.
• Mould and pinch the cheese into a ball about 3cm wide, then drop it into a bowl of chilled water. Repeat with the remaining curds, refrigerate and use within two days.