Why the apple is green and very sour
Red to green is the iron ion oxidation reaction in apples
There are two reasons for both inside and outside. Internal causes of these apples are containing a kind of anthocyanins, anthocyanins increase will appear red. On the contrary, less will become green. External is the sun, when the sun shines on the apple, the irradiated side of the anthocyanin will be a lot of increase. In this way, the apple side of the sun will gradually become red. In contrast, the other side appears to be more green. As for some of the apples (such as bananas) no matter how the sun, it will not turn red, because they contain less leaves, with lutein is also more apples are ripe yet red, so the color does not seem to play What big effect. At present, although it is not clear why this is the reason, but in any case, the fruit is because with the leaves, safflower pigment the same pigment is more and more into the red. Many fruit ripening will produce a lot of sugar, so become very sweet. Apple's red pigment with apple sugar is closely related. It can be said that with the increase in sugar, the pigment is also increasing, green apple sugar less, so will acid!
