How do fruits change taste and color during ripening?

Posted on Mar 9, 2022      249

Fruits and vegetables come in all kinds of colors! And each of them has its own bright and unique taste. But until the fruit ripens, almost all of them look alike: green, hard and sour. What is ripening, during which the taste and color of the fruit changes?

So, at first, the fruit is green because it contains an enormous amount of chlorophyll, the green pigment involved in photosynthesis. At some point, ethylene gas, a natural plant hormone, is produced inside the fruit.

This is interesting: Ethylene gas is produced by the fruit itself, not the plant. Therefore ripe green fruits ripen. This peculiarity of fruits and vegetables comes in handy in commercial transportation, when fruits that are picked still green ripen during transportation.

After ethylene gas is produced, the ripening process of the still-green fruit begins

Ethylene acts on the fetus’s receptors, which activate certain genes. The fruit produces enzymes: β-Amylase, which breaks down starch to sugars, making the fruit less acidic, and pectinase, which affects the structure of the fruit by softening it. Chlorophyll is broken down by hydrolases (hydrolytic enzymes), causing the fruit to lose the green color associated with immaturity. From this point on, fruits and vegetables take on their usual color: some pigments hidden up to this point by chlorophyll are revealed, plus new ones are synthesized. The two major culprits for a fruit getting color are carotenoids, responsible for orange and yellow colors, and anthocyanins, which give the fruit its red and blue colors.

That’s the number of complex chemical processes that go on in some little grape before it reaches our mouths.