Why do apples turn brown after you cut them open?

Answer 1

That's the cyanide in them seeping out.

"....are poisonous, containing a small amount of amygdalin, a cyanogenic glycoside...."

Answer 2

the discoloration that occurs in apples is the work of an enzyme called polyphenolsoxidase, which oxidize phenolic compounds in the tissue and causes them to condense into brown or grey polymers. A similar kind of enzyme acting on a similar kind of compound is responsible for the "browning" of humans in the sun. Polyphenoloxidase is also present in mushrooms, apricots, pears, cherries, peaches and dates, but is missing from citrus fruits, melons and tomatoes. These fruits will eventually turn brown simply by the action of oxygen in the air, but the chemical reactions are much slower without polyphenoloxidase, and it takes days for their color to change.In intact tissue, the enzyme and the phenolic compounds are segregated, but when cells are disrupted, they come into contact with each other and react to form dark pigments. Enzymatic browning can be discouraged by several means. Chilling the food below 40* F will slow the enzyme down. Even better boiling temperatures will destroy it, but this means cooking and so altering the flavor of the fruit or vegetable. Lemon juice is the best bet.

Answer 3

its called oxidation:

Fresh cut apples turn brown when iron-containing chemicals inside apple cells react with oxygen in the air. We see this every day when iron objects rust, or when scabs on cuts turn brown.

Answer 4

It's like when u get a cut and bleed. When that blood is hit with air, it turns into dry blood, and a scab. Well since an apple isn't; skin, and cant form a scab, then it rotts, and turns brown. Hope I helped! PeAcE!

Answer 5

The same reason the blue blood in your veins turns red when cut open. It's a reaction to oxygen.

Answer 6

i do know that it has something to do with the chemicals or acids you could say in the apple mixing with the carbon dioxide in the air that it automatically makes the apple turn brown. i think that pretty much goes for any fruit to be honest with you.

Answer 7

It's called oxidation and is caused by a reaction with the oxygen in the air. It's the same reaction that makes rust.

Answer 8

Oxygenation

Answer 9

Oxygenation

Answer 10

Air is an oxidizer the same reason metal rusts when exposed to air