You're gonna get some juice. Watery, red liquid seeps out of the meat and on to the plate and it kind of looks like blood.

But I have good news for people

who like to eat red meat but don't like to eat blood

It's not blood.

It's just water plus a handy protein called myoglobin.

All meat is muscle but the muscle looks different

depending on what it's used for

White meats like turkey and chicken come from muscles

that are used in short spurts every so often

but have to get moving quickly

Think of the chicken breasts

They don't actually use their wings very often

Red meats like beef, lamb and even pork come from muscles used for long strenuous activities

like carrying a huge cow around all the time

Before cooking,

these meats are a pinky, reddish color.

Holding up a heavy cow is some serious work.

Work that requires a lot of oxygen for fuel

which is where myoglobin comes in

Myoglobin is a special protein

with an iron atom at its center,

which bonds with, then stores and delivers oxygen to muscle cells

It works together with hemoglobin, another oxygen carrier

to get oxygen to the cells that needed.

The difference between red meat and white meat

comes from the levels of myoglobin in the muscle.

And myoglobin protein itself is red

so the more myoglobin in the cells the redder the meat appears.

And that juice that's spilling out of your meat?

That's a combination of water and myoglobin.

The animal's blood was removed when the meat was processed.

Beef is around 0.8% myoglobin and lamb has a little less at 0.6%.

And all of those ads have been lying to you

because at 0.2% myoglobin

pork is generally considered red meat too.

Chicken only has about a quarter of that amount

But what about humans?

Well, our flesh is about as red as red meat can get

at 2% myoglobin.

If you have been like steak

but you don't want red juice

you have options.

Myoglobin is red when it's bonded with oxygen.

When meat is cooked rare,

up to about 60 degrees Celsius,

the color stays

Above that temperature,

the iron atom in myoglobin loses an electron,

and therefore its ability to bind with oxygen.

Instead, the myoglobin forms a new molecule

called hemichrome

that gives medium and well done meet its brown gray color

Myoglobin will also turn brown

if it's exposed to air for long enough,

because that makes the iron atoms lose an electron too.

Which is why checking the color

can be a handy way to tell

if your store-bought meat is still fresh

It doesn't always work though,

because some meat producers add compounds

that keep the meat red and the color can last way past the expiration date.

But if you do end up buying that red meat and cooking it rare,

I hope you enjoy your oxygen rich protein water.

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