Blueberries may appear blue on the outside, but what color are they on the inside? The inside flesh of blueberries can range from shades of purple to almost deep red. The pigments that give blueberries their color are anthocyanins, which also act as antioxidants that provide the berries’ health benefits. So while blueberries may be blue on the outside, their insides reveal a more complex palette of purple hues.
What gives blueberries their color?
Blueberries get their signature blue hue from natural pigments called anthocyanins. Anthocyanins belong to a class of antioxidant compounds called flavonoids. These water-soluble pigments are found in the skin and flesh of blueberries and other berries like blackberries, raspberries, and strawberries. Anthocyanins act as antioxidants that protect plants from damage and disease. When eaten, they also provide antioxidant effects and health benefits for humans.
The specific anthocyanins found in blueberries include:
- Malvidin
- Delphinidin
- Petunidin
- Peonidin
- Cyanidin
The concentration and types of anthocyanins present determine the exact shades of blue, purple, or red of the blueberry’s skin and flesh. The pH level also affects the pigment, causing it to appear more red in acidic conditions. While malvidin gives blueberries their signature blue, as pH decreases, the color shifts toward reddish tones.
What color are blueberries inside?
Cut open a blueberry and peek inside – the flesh is not blue at all! The interior of blueberries can range from greenish to deep crimson or purple as the anthocyanin pigments permeate the flesh. Some varieties have a lighter green color toward the center.
Here are the different colors you may see inside different types of blueberries:
| Type | Inside Color |
|---|---|
| Highbush | Greenish-white to light purple |
| Rabbiteye | Green with reddish purple flesh |
| Northern Highbush | Pale green to purple |
| Southern Highbush | Dark purple flesh |
The most common types eaten fresh – Northern and Southern highbush – tend to have deep purple pigmentation internally. Rabbiteye varieties retain more green flesh while highbush ranges from greenish to purplish.
What impacts blueberry color?
Several factors impact the color of a blueberry’s flesh and skin:
Maturity: Unripe green berries become blue/purple as they mature. Fully ripe blueberries have the deepest color.
Growing conditions: Cooler night temperatures promote anthocyanin development and deeper purple/red hues. Warm days and plenty of sunlight also increase anthocyanins.
pH: Anthocyanins change color based on pH. More acidic conditions make blueberries appear redder. Higher pH causes more blue/purple tones.
Berry variety: The type of blueberry impacts color based on anthocyanin content. Some varieties are naturally deeper purple inside and out.
Storage: Freshness and storage conditions affect color. As moisture is lost, the purple hues become muted.
Freezing or dehydrating blueberries also intensifies the anthocyanins as the berries thaw or rehydrate, creating very dark purple juice.
Are wild blueberries different colors?
Wild blueberries tend to be smaller than cultivated blueberries with a slightly more intense color. This is because wild blueberries grow naturally in harsher conditions that stimulate anthocyanin production. The cool temperatures, high sunlight, and acidic soil of northeastern US and Canada where wild blueberries grow foster deep purple pigments.
Wild blueberries are typically deep indigo blue on the skin with a dark burgundy or deep purple interior flesh. They have a higher concentration of antioxidants compared to cultivated blueberries. Though smaller, they pack a big punch of vibrant color and flavor.
Do white and pink blueberries exist?
While most blueberries are shades of blue, purple, or red, there are some exotic and genetically engineered varieties that produce white or pink berries!
White blueberries occur naturally but are extremely rare. They have a genetic mutation that prevents anthocyanin formation, creating a white berry. The first documented white blueberry bush was found on a farm in New Jersey in the 1900s. Since then, breeders have cultivated more white blueberry varieties like Crystal, Ice, and Snowflake developed at Rutgers University.
Pink blueberries do not occur naturally but have been genetically engineered. By reducing expression of the gene for anthocyanin biosynthesis, researchers have created pink-hued blueberries. These unique berries retain their other blueberry-like qualities and antioxidant capacity despite the color change. They provide a novelty color for consumers.
Both white and pink blueberries lack the beneficial anthocyanins of their blue counterparts. While an interesting novelty, they do not offer the same nutritional benefits.
Conclusion
While blueberries live up to their name coloring the skin in shades of blue and purple, inside they reveal a more dynamic range of hues. Their color depends on the natural pigments called anthocyanins that act as antioxidants and offer health benefits. The exact ratio and types of anthocyanins, along with growing conditions and berry variety, determine the resulting color profile. Ranging from light green to deep crimson or purple, the inside of a blueberry can span the rainbow! So savor a bowl of blueberries, and appreciate the diverse palette displayed inside each bite.
