- Pour the milk into the pressure cooker. Cover and select the Yogurt function. Set the machine to cook for 8 hours.
- After 1 hour (the pressure cooker will beep after 1 hour of cooking), remove the lid. Using a spatula, stir in the yogurt starter. Cover and continue cooking for 7 hours.
- Remove the lid. Transfer the yogurt into an airtight container. Cover and refrigerate for 4 hours or until completely chilled. The yogurt will keep for 2 weeks in the refrigerator.
- For Greek yogurt, line a large sieve with coffee filters and set it over a bowl. Pour the hot yogurt into the lined sieve. Cover with plastic wrap and let drain in the refrigerator for 4 hours or until completely chilled. Discard the liquid. Transfer the chilled yogurt to an airtight container. The Greek yogurt will keep for 2 weeks in the refrigerator.
For a richer, creamier yogurt, replace 1 cup (250 ml) of the 3.25% milk with the same quantity of 35% cream. Depending on the type of yogurt starter used, the fermentation time may vary from 8 hours (for the orange box) to 15 hours (for the green box).