Have you ever wondered why blueberries are blue? Where do blueberries get their color from? What exactly makes blueberries blue and not red or purple or white? Are blueberries naturally blue or are they GMO? How do blueberries come to be blue? Are there other blueberry colors aside from blue?
What color are blueberries?
First thing first: what is the color of blueberries? Officially, blueberries are blue. This is also the reason why they are called blueberries – because they’re blue.
However, blueberries contain more than just blue pigments: there are green, red, blue and purple pigments in blueberries. The content of the various pigmented constituents fluctuates throughout the ripening process which explains why blueberry color fluctuates too throughout the ripening process.
Unripe blueberries are a pale green color; underripe blueberries are pale green tinged with pink at first and slowly turn a more uniform pink-purple color.
As the berries begin to ripen, the blue pigment starts to accumulate in the blueberries and they become blue. Fully ripe blueberries should be blue all over on the outside.
There are two major varieties of blueberries: American and European. While American blueberries are a more straightforward blue color, European blueberries (also called bilberries) are more of a blue-black color when ripe.
Also, another big difference between American and European blueberries is that American blueberries are greenish white inside, while European blueberries are a dark reddish-purple color.
Where does the color in blueberries come from?
Ripe blueberries are blue in color, or a darker black-blue if we’re talking about European blueberries, but blue nonetheless. Where does the blue color in ripe blueberries come from? Ripe blueberries owe their particular color to pigmented blue antioxidants.
The blue pigments in blueberries belong to a larger class of pigments called anthocyanins. Anthocyanins come in several colors and account for the bulk of colors in food and nature, including pink and red, purple and violet, and blue and black.
Blueberries too owe their color to blue anthocyanins, as do Aronia berries, also known as chokeberries, black mulberries, Concord grapes, Amelanchier berries, blackberries and black raspberries, and purple raspberries too.
Research notes the presence of ‘different types of anthocyanins’ in blueberries, ‘including malvidin, delphinidin, petunidin, cyanidin and peonidin, with the sugar moieties of glucose, galactose and arabinose’ (source).
‘According to some findings, malvidin and delphinidin are the major components and might constitute almost 75% of all identified anthocyanins (source). However, other findings postulated that the percentage of delphinidin is 27%–40%, malvidin 22%–33%, petunidin 19%–26%, cyanidin 6%–14% and peonidin 1%–5%’ (source 1 , source 2).
Malvidin gives either a blue, or a red or purple color to edible and ornamental plants. Malvidin is partly responsible for the blue pigmentation in American blueberries (skin), European blueberries (skin and flesh), and also Amelanchier berries, dark-colored grapes and chokeberries.
Delphinidin also gives off either a blue or red color. Delphinidin is responsible for blue and blue-red colors in edible and ornamental plants, including American blueberries, skin only, and European blueberries, skin and flesh which is a dark reddish purple color as opposed to the flesh of American blueberries which is a greenish white color.
How do blueberries come to be blue?
Blueberries are initially a pale green color when unripe. As blueberries begin to ripen, they start to accumulate other pigments, pink-red and purple at first and then blue.
The more the ripening process advances, the more blue pigments accumulate in the berries and the more pregnant the blue color becomes superseding all other lighter pigments.
Are blueberries GMO?
A big question on people’s minds is whether or not blueberries are GMO.
Despite potential concerns, blueberries are naturally blue.
In fact, color is common in nature, from inedible and edible plants to animals (think violets, petunias, morning glories, chokeberries, blue and black grape varieties, purple raspberries, black raspberries or blackberries, salmon and flamingoes).
The same class of pigmented constituents that give blueberries their color naturally is present in most of the foods we regularly eat.
In fact, the exact same types of pigments occurring naturally in blueberries are also found in Aronia berries or chokeberries, Amelanchier berries or saskatoon or serviceberries, Concord grapes, muscadine grapes, black tomatoes, purple tomatoes or blue tomatoes (e.g. the Indigo Rose tomato).
Why are blueberries blue?
Blueberries are blue because they have predominantly blue pigments when ripe. As simple as that.
As blueberries ripen, they start to accumulate pigments, including red, purple and blue.
Blue pigments accumulate more and more towards the later part of the ripening process which is when blueberries begin to turn blue.
The more the ripening process advances, the more blue pigments accumulate in the berries and the more pregnant the blue color. At the point they’re ripe, blueberries have predominantly blue pigments.
Does blueberry color affect nutrition?
Is the natural color of blueberries a source of nutritional or health benefits? The dark color of blueberries indicates the presence of high amounts of pigmented anthocyanin antioxidants which studies confirm have a range of biological activities.
Among the scientifically-proven biologically active effects of anthocyanins are free radical-scavenging, anti-inflammatory, antiproliferative and reparative actions.
Are there other blueberry colors?
No, all types of blueberries are the same color when ripe: blue. The only difference is that American blueberries are a more straightforward blue, whereas European blueberries, or bilberries, are more of a black-blue. But only on the outside (the peel or skin).
On the inside, American blueberries are a greenish white, while European blueberries are a dark reddish purple color.
