Oranges come in a variety of colors, ranging from yellow to deep orange. While many people may think of oranges as being a solid orange color, there are actually distinct varieties that produce yellow/green-skinned fruit.
What determines orange color?
The color of an orange is primarily determined by the relative levels of carotenoid pigments in its skin and flesh. The main carotenoids that contribute to orange color are:
- Beta-carotene: Produces rich orange/yellow colors
- Beta-cryptoxanthin: Produces yellowish hues
- Zeaxanthin: Produces yellow tones
Oranges with higher levels of beta-carotene appear more orange, while those with higher levels of beta-cryptoxanthin and zeaxanthin take on yellow tones. Climate and variety also impact concentrations of these pigments.
Yellow orange varieties
There are a few varieties of oranges that naturally produce yellow to greenish-yellow skin:
- Green oranges – A tart, acidic variety that originates from Australia. Skin remains yellow-green at maturity.
- Bitter oranges – Used for marmalades and liqueurs. Thick, pitted skin turns yellow when ripe.
- Chinotto – A small, sour Italian variety with yellow-green skin.
- Bergamot orange – Grown for its aromatic oil. Greenish-yellow skin and very sour juice.
While many other orange varieties turn yellow as they over-ripen, these types have yellow skin when optimally ripe.
Why are some oranges yellow?
There are a few reasons why certain orange varieties have yellow skin:
- Higher levels of zeaxanthin and beta-cryptoxanthin compared to beta-carotene. These carotenoids produce yellow/green hues.
- Thicker peels containing more chlorophyll, masking deeper orange tones.
- Cooler nighttime temperatures during fruit development, which favors accumulation of yellow pigments.
- Early harvest, before deeper orange colors fully develop.
- Genetic factors regulating carotenoid biosynthesis in each variety.
The same pigments that color the skin also determine inner flesh color. Therefore, yellow-skinned oranges will typically have paler flesh than orange-skinned varieties.
Other ways oranges turn yellow
While some varieties naturally produce yellow to greenish skin, oranges can also turn yellow due to:
- Overripening – Excess ripening depletes deep orange carotenoids, revealing underlying yellow tones.
- Cool temperatures – Storage in cold rooms causes chlorophyll levels to increase, masking orange hues.
- Sunburn – Damages dark orange outer peel, exposing lighter interior layers.
- Fruit fly damage – Larval feeding breaks down orange pigments, causing yellow spots.
- Sinkholes – Depressions in the peel turn yellow as oranges age on the tree.
While these environmental factors can yellow the skin, the inner flesh often retains much of its original orange color.
Popular yellow orange varieties
Some of the most common yellow orange varieties include:
| Variety | Description |
|---|---|
| Bergamot orange | Grown for its aromatic oil, which is used to flavor tea. Inedible yellow-green flesh. |
| Bitter orange | Used to produce marmalade. Yellow skin and sour juice. |
| Chinotto | An Italian specialty orange. Small, very sour with thick yellow-green peel. |
| Green orange | A tart, acidic variety from Australia. Retains yellow-green skin when ripe. |
These varieties all contain higher levels of zeaxanthin and beta-cryptoxanthin compared to traditional oranges. Their distinctive flavor and appearance make them popular for culinary use.
Uses for yellow oranges
The tart, aromatic qualities of yellow oranges make them suitable for specific culinary applications:
- Marmalades and preserves – Yellow varieties like Seville and Bergamot are often used due to their distinctive tangy flavor.
- Liqueurs – The peels of yellow oranges can flavor drinks like Triple Sec.
- Aromatic oils – Cold pressing bergamot peels makes an oil ideal for perfumery.
- Marinades and dressings – Juice and zest can provide tangy, citrusy flavor.
- Candying peels – The thick, pitted peels of yellow oranges make tasty candied treats.
While often too sour to eat raw, these oranges come into their own when cooked, candied or turned into drinks.
Nutrition of yellow vs. orange oranges
Despite color differences, most orange varieties share a similar nutritional profile. A medium orange of either color provides:
| Nutrient | Amount |
|---|---|
| Calories | 62 |
| Carbs | 15 grams |
| Fiber | 3 grams |
| Vitamin C | 70 mg (78% DV) |
| Folate | 38 mcg (10% DV) |
| Potassium | 237 mg (5% DV) |
The main nutritional differences relate to carotenoid content. Yellow oranges contain more zeaxanthin while traditional oranges harbor higher levels of beta-carotene. Both offer vitamin C, potassium, folate and fiber.
Selecting yellow oranges
When selecting yellow oranges, look for:
- Firm, heavy fruit with thin, fine-grained skin.
- Intensely colored yellow skin, depending on variety.
- Noticeable fragrant citrus aroma.
- Smooth skin free of blemishes, bruising, or soft spots.
- Avoid oranges with greenish patches or gray mold.
Size is not an indicator of quality or flavor. Both small and large oranges can be juicy and sweet if optimally ripe.
Ripening and storing
Like other oranges, yellow varieties will not ripen further once harvested. Mature fruit should be left at room temperature until ready to eat. To extend shelf life:
- Store unwashed oranges in the crisper drawer of the refrigerator for 2-3 weeks.
- Place them in a mesh bag or perforated plastic bag.
- Keep humidity around 90% to prevent moisture loss.
- Avoid freezing whole oranges, which damages the peel and flesh.
With proper storage, ripe yellow oranges will retain their flavor, juiciness and nutritional quality for several weeks.
Conclusion
While not as common as the bright orange navel and Valencia varieties, yellow oranges offer unique culinary qualities. Varieties like Bergamot and Bitter oranges have distinctly aromatic peels and tart juice perfect for marmalades, liqueurs and candied fruit. With proper selection and storage, these flavorful yellow oranges can be enjoyed long after harvest.