What Happens to Meat When You Cook it?
Red meat contains myoglobin which turns brown during
the cooking process. (Image Andy Ciordia).
Meat is animal muscle, 75% of which is water. The rest is protein (about 20%) and fat (5%), as well as small amounts of carbohydrates, acids and minerals.So what happens when a piece of raw meat goes on a hot frying pan?The protein molecules are in bonded coils, but as heat is applied the bonds break and the coils start to unwind.Meanwhile much of the water content in the muscle fibres leaches out – that’s why your fillet steak or chicken breast is smaller after cooking than when it is raw.If it’s red meat (lamb, beef) it begins to turn brown as the myoglobin reacts to the heat. Similar to haemoglobin, myoglobin is a protein that stores oxygen in red blood cells. Heat triggers iron atom oxidation. The iron atoms in the protein lose an electron and this gradually changes the colour from red to brown.White meat (chicken, turkey) has far less myoglobin, so it is pink when raw and turns white when cooked.