How do I know if I need to use Calcium Chloride?
milk that has been pasteurized and cold stored should have Calcium
Chloride (CaCl) added. The reason for this is because the calcium
originally in the milk slowly becomes soluble and cannot be used to form
a firm curd. The exception is Mozzarella because the stretch depends on
the calcium leaving the curd. Some fresh milks may need CaCl added if
the curd is not firm enough due to poor calcium in the milk, caused by
either season or poor diet.
This information applies to both hard and soft cheeses.