What is the white membrane of an orange called?

November 28, 2025 •

4 min read

Most people assume the white membrane found inside an orange is flavorless, or worse, bitter, and throw it away without a second thought. However, the fibrous, sponge-like substance is technically known as the orange pith, or albedo. Despite its unappealing appearance to some, this often-discarded part of the fruit holds a surprising concentration of nutrients that are highly beneficial for your health.

Quick Summary

The white membrane of an orange is called pith or albedo. It is a fibrous layer located between the peel and the fruit's segments, packed with fiber, antioxidants, and vitamins. Far from being useless, it offers significant nutritional value for gut and heart health.

Key Points

Name of the membrane: The white membrane of an orange is called the pith, or more technically, the albedo.
Nutritional density: The pith is a concentrated source of dietary fiber, including pectin, and contains powerful flavonoid antioxidants like hesperidin.
Health benefits: Consuming the pith can support heart health by improving blood vessel function and aid digestive health through its high fiber content.
Flavor profile: Contrary to popular belief, orange pith is not intensely bitter and is often tasteless, with the bitter reputation more applicable to grapefruit pith.
Culinary uses: The pith can be incorporated into smoothies for added fiber, used as a natural thickener in marmalades, or added to homemade candied peels.
Comparison with zest: The pith is the spongy white layer, while the zest is the thin, aromatic outer orange layer. They offer different nutritional and flavor profiles.
Preparation tips: To avoid any potential bitterness and maximize nutritional intake, consider adding the whole orange (peel and pith included) to a blender for smoothies, particularly if using organic fruit.

Pith vs. Albedo: What's in a Name?

While "pith" is the common term used for the white, spongy material under the orange's peel, its scientific name is the albedo. It is distinct from the zest, which is the thin, outermost colored layer of the peel. The albedo serves a crucial purpose in nature, protecting the fruit's juicy flesh. Within this protective layer and the connecting strands, a wealth of nutrients is hidden, which is often mistakenly discarded during peeling.

The Nutritional Powerhouse You've Been Throwing Away

An orange is widely recognized for its high vitamin C content, but many are surprised to learn that the pith contains a comparable amount of this immune-boosting vitamin. But its nutritional benefits don't stop there. Here's a list of reasons to reconsider discarding the pith:

High in Dietary Fiber: The fibrous nature of the pith is due to its rich concentration of pectin, a soluble fiber. This fiber aids digestion, helps regulate blood sugar levels, and can help lower cholesterol.
Source of Potent Antioxidants: The pith contains powerful flavonoid antioxidants, such as hesperidin. These compounds help protect your body's cells from damage caused by free radicals and have significant anti-inflammatory effects.
Supports Heart Health: The hesperidin found in the pith has been shown to support cardiovascular health by helping to relax blood vessels, which may contribute to lower blood pressure.
Contributes to Gut Health: Pectin acts as a prebiotic, which feeds the beneficial bacteria in your gut. A healthy gut microbiome is essential for overall well-being.
Slows Sugar Absorption: Research indicates that the flavonoids in the pith can help delay the absorption of natural sugars from the orange, potentially leading to a more controlled blood sugar response after eating.

Flavor Perception and the Pith

For many, the biggest deterrent to eating the pith is its perceived bitter taste. Interestingly, studies have revealed that the pith of oranges is almost tasteless, or at most, only mildly bitter. The myth of the intensely bitter orange pith may stem from the fact that grapefruit pith is genuinely quite bitter. In other cases, when the zest and pith are rubbed together, enzymes can create more bitter compounds. The solution? Properly separating the two or incorporating the whole food into smoothies or recipes where the taste is masked.

Comparison: Pith vs. Zest

Understanding the roles and properties of the different parts of the orange peel can help you maximize its use in cooking and for health. Here is a comparison of the orange pith (albedo) and the zest (flavedo).


Feature	Orange Pith (Albedo)	Orange Zest (Flavedo)
Location	The white, spongy inner layer of the peel.	The thin, outer colored layer of the peel.
Flavor Profile	Almost tasteless to mildly bitter, spongy.	Intense, citrusy, and aromatic due to essential oils.
Nutritional Value	High in fiber (pectin), vitamin C, and flavonoids like hesperidin.	High in essential oils, vitamin C, B vitamins, and antioxidants.
Best Culinary Use	Marmalades, jams (as a thickener due to pectin), smoothies (for added fiber).	Flavoring cakes, cocktails, dressings, and desserts.
Key Function	Protects the fruit and provides bulk/fiber.	Contains aromatic oils and protects against insects.

Culinary Applications and Preparation

There are numerous ways to incorporate the nutritious pith into your diet, moving past the common misconception of it being inedible or unpleasant. You can easily include it in smoothies, where the other ingredients mask its texture. For savory dishes, dried orange peel (including the pith) can be ground into a spice blend, adding depth of flavor. For those with a sweet tooth, candied orange peels, where the pith is boiled to remove bitterness, can be a delicious treat.

Simple Pith-Free Peeling Method

If you prefer to remove the pith for a smoother finish, you can do so easily. One method involves using a sharp paring knife to slice off the top and bottom of the orange. Then, run the knife down the sides to remove the remaining peel and pith in strips, following the curve of the fruit. A quicker, though more unusual, technique involves boiling the orange for just ten seconds before peeling, which loosens the pith from the fruit segments.

Conclusion: Don't Discard the Goodness

Next time you peel an orange, consider the white membrane—the pith or albedo—not as an obstacle, but as an opportunity. This nutrient-dense, fiber-rich, and antioxidant-packed part of the fruit has significant benefits for your cardiovascular and digestive health. By embracing this often-overlooked component, you can enjoy the full, complete goodness that nature's citrus has to offer, turning a simple snack into a nutritional power boost. Whether you blend it into a smoothie or add it to marmalade, giving the pith a second chance is a wise, and healthy, choice.

Frequently Asked Questions

Yes, the white membrane of an orange, known as the pith or albedo, is completely edible and offers numerous health benefits.

Contrary to a common myth, the pith of most oranges is either tasteless or has only a very mild bitterness, with the strong bitter flavor typically associated with grapefruit pith.

The orange zest is the thin, outer, brightly colored layer of the peel, containing aromatic oils, while the pith is the spongy, white layer found beneath the zest.

Orange pith is rich in dietary fiber, including pectin, and flavonoid antioxidants like hesperidin. These compounds help regulate blood sugar, lower cholesterol, aid digestion, and protect against cellular damage.

You can include orange pith in your diet by blending it into smoothies, using it to make marmalades, or preparing candied citrus peels, where the bitterness can be reduced through boiling.

Yes, the pith contains a significant amount of vitamin C, comparable to the juicy fruit segments, along with other nutrients.

One common method for removing pith is to use a sharp knife to first cut off the top and bottom of the orange, and then slice the peel and pith away in strips, following the fruit's curve. A quick boil can also help loosen it.

Hesperidin is a powerful flavonoid antioxidant that is highly concentrated in the orange's pith and membranes. It is known to support heart and brain health.

The orange pith is rich in pectin, a type of soluble fiber that promotes healthy digestion by supporting a beneficial gut microbiome and regulating bowel movements.

Yes, those white stringy parts are also pith and are perfectly safe and healthy to eat. They are rich in fiber and antioxidants.