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Collagen and gelatin

Why tough cuts become tender and rich with long, moist cooking.

70โ€“95 ยฐC (158โ€“203 ยฐF)

What it is

Connective tissue is mostly collagen, a tightly wound protein that is chewy when raw and contracts when first heated โ€” which is why a braise seems to get tougher before it gets tender. Held above about 70 ยฐC in the presence of water, it unwinds and hydrolyses into gelatin, which is soft and holds water.

Why it works

The conversion is slow and depends on both temperature and time. Higher heat is faster but squeezes more water out of the muscle fibres, so the meat can end up tender and dry at once. A long hold at a low temperature converts collagen while losing less moisture.

When to use it

Shoulder, shin, cheek, oxtail, ribs, neck, feet, skin โ€” every cut that hard work made tough.

What goes wrong

Cooking to a temperature rather than to a texture: a braise is done when a fork meets no resistance, which may be two degrees and ninety minutes past where it looked done.

Meridian cooking encyclopedia โ€” Watchman Productions

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