Asked by: Anonymous
Cheese is made by adding an enzyme called rennet to milk, then straining the curd from the whey. This gives you a mixture of milk fat held together with proteins – mainly casein. Fresh cheese contains lots of water so it’s soft and delicate.
As it matures into cheddar, the water evaporates and the cheese becomes firmer. After a week or two, you have mild cheddar, which is quite strong and elastic as the casein holds it together. But some rennet is always left behind and manufacturers often inject other enzymes as well. These slowly break down the casein as the cheddar matures. Mature cheddar is crumbly because it’s drier, but also because it doesn’t have as much casein reinforcement.
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