Rescues · TO GRATE
Cheese melts into a stringy, oily mass anyway.
Why it happens
Pre-grated cheese, which is coated in starch or cellulose to stop it caking, and that coating interferes with a smooth melt.
Recovering it
A wet grated mixture is fixed by squeezing hard in a cloth, and the liquid is worth keeping in the potato case — the starch settles out of it and is the best binder available. Cheese that has seized in a sauce comes back with a splash of cold liquid whisked in off the heat. Discoloured potato is cosmetic and disappears on cooking.
The mechanism
Grating does one of three jobs depending on what is being grated. For cheese it is about melting: shreds have far more surface area than a block, so they melt at a lower pan temperature and in a fraction of the time — which matters because cheese held above roughly 65°C tightens and squeezes out its fat, and anything that shortens the time above that threshold protects the texture. For hard vegetables it is about water: a grated potato or courgette releases moisture almost immediately through all those ruptured cells, which is why grated vegetables are salted and squeezed before they go into a fritter or a slaw. For aromatics it is about dispersion — grated garlic or ginger distributes evenly in a dressing where minced would sit in pockets.
The full TO GRATE lesson — how to tell, where to practise it, what it carries to.