NOTE that this is not a cultured mozzarella, which is more authentic and flavorful, but is a good place to start. A cultured mozzarella does not use citric acid but a thermophilic culture instead and is a longer process.
1 US gallon (3.8 L) whole milk (not ultra-pasteurized)
1½ tsp citric acid, dissolved in ¼ cup (60 mL) cool water
¼ tsp liquid rennet, dissolved in ¼ cup (60 mL) cool, non-chlorinated water
1–2 tsp cheese salt
Making the curds
- Pour the milk into a large pot and stir in the dissolved citric acid.
- Slowly heat to 32°C (90°F), stirring gently.
- Remove from the heat and stir in the dissolved rennet using an up-and-down motion for about 30 seconds.
- Stop stirring and let the milk sit undisturbed for 5–10 minutes, until you have a clean break.
- Cut the curd into roughly 2 cm (¾") cubes.
- Slowly heat the curds and whey to 40°C (105°F), stirring very gently.
- Remove from the heat and let the curds rest for about 5 minutes.
- Scoop the curds into a colander and allow them to drain.
Stretching
- Heat a separate pot of water (or, even better, the strained whey) to about 77–82°C (170–180°F).
- Place the drained curds in a bowl and:
- Pour enough hot whey over them to cover.
- Let them sit for 20–30 seconds.
- Lift the curd with a spoon or your hands (wear gloves if needed—it will be hot).
- Fold and stretch it gently.
- If it begins to stiffen, dip it back into the hot whey for another 20–30 seconds.
- Repeat until the curd becomes smooth, glossy, and stretches into long ribbons.
- Knead in the salt during the last stretch.
- Form into balls and cool in cold water for 10–15 minutes.