Why is okra so slimy? Blame the mucilage.

Okra is one of those vegetables with a polarizing reputation. Whether you call it slimy, gooey, sticky, or slippery, if you’ve eaten okra, you probably have an opinion about its unique texture, which is more properly described as “mucilaginous.”

Some okra recipes strive to minimize slime; others celebrate and embrace the thickening it provides to dishes like Louisiana gumbo. But did you ever wonder why okra is so gooey? What’s the source, and what purpose does it serve for the okra plant?

Mucilage protects okra seeds

The edible part of okra is the plant’s immature seedpods, which contain high levels of a substance called mucilage. Food science writer Harold McGee described mucilage in his book On Food and Cooking: The Science and Lore of the Kitchen as “a complex mixture of long, entangled carbohydrate molecules and proteins that helps plants and their seeds retain water.” Basically, mucilage is the watery slime around the okra seeds. As the seeds develop, their moist coating protects them from drying out.

Okra likely evolved its slime (or, more accurately, mucilage) as a water-conserving adaptation for growing in hot, dry climates. McGee notes that the okra plant “originated in either southwest Asia or eastern Africa, and came to the southern United States with the slave trade.” Today, okra is popular in many tropical and subtropical regions of the world, and is known for its high tolerance to heat and drought when compared with other crops. 

Mucilage is found across the plant world

Okra is not the only plant with goo-producing levels of mucilage. It’s a common feature of desert plants like cacti and succulents, which have a similar need to store water. Other edible examples include some seaweeds, and leafy greens such as Malabar spinach, native to Asia, and molokhia, popular in parts of Africa and the Middle East.

Mucilage is actually produced in smaller quantities by almost all plants, as well as by some microorganisms. Single-celled protists like amoebas propel themselves on a trail of mucilage, similar to the slime trail of a snail. Japanese natto, made from fermented soybeans, gets its signature stretchiness from bacterial cultures. 

“The majority of plants produce mucilage from the seed coat,” according to a 2021 research review. However, the way that mucilage keeps seeds moist can vary. While okra seeds grow inside a mucilage coating, in other plants, mature seeds that have been shed produce mucilage by absorbing water from their surroundings. You can see this yourself when you soak chia seeds to make a chia pudding, or flaxseeds to make a “flax egg” for vegan baking. Each tiny seed sucks up water to form a layer of mucilage, creating a gel-like texture.

There are also other ways plants use mucilage beyond water conservation. Carnivorous sundews use droplets of mucilage as glue traps for insects. Sierra Mixe or olotón, an heirloom variety of corn from Oaxaca, Mexico, has exposed roots that drip with mucilage. This slime shelters symbiotic nitrogen-fixing bacteria. As a result, says a 2020 UC Davis report, “Sierra Mixe corn receives much of the nitrogen it needs from the atmosphere,” and thrives in nitrogen-poor soil.

People have many uses for mucilage, too

The human uses for mucilage go far beyond food. Historically, plant mucilage was used as a natural hair gel, and as an adhesive for paper stamps and labels. In medicine, mucilage can act as a demulcent, a substance that soothes irritated mucus membranes by forming a protective layer over them. Examples include slippery elm tea for sore throat and aloe ointment for sunburn. Mucilage is also the active ingredient in fiber supplements such as psyllium husk, and is found in some cosmetics.

Scientists also increasingly look to mucilage for industrial purposes. A 2021 research review describes plant mucilage as “a renewable and cost-effective source of plant-based compounds”  that are both biodegradable and environmentally friendly. In the case of okra specifically, its mucilage has been used to make biodegradable food packaging film and for filtering particles from wastewater.

How to handle mucilage when cooking okra

Some cultures actively celebrate mucilage as a part of the culinary experience. In Japan, the texture of ingredients like okra and natto, known as neba-neba, is prized. In Nigeria, dishes made with okra and other viscous ingredients are called “draw soups,” because they’re so thick they draw back into the pot on their own when lifted. However, some don’t like the slimy texture, which is why there are many methods to make okra less slimy in the kitchen, rather than more so. 

Science writer Jared Levan noted in a 2018 article for Food Republic that “mucilage’s viscosity increases when heat is applied.” Short cooking preparations of okra, such as frying or sauteeing, release less mucilage than long ones, such as stewing. Adding acidic ingredients like tomatoes to okra also helps reduce the slime. And because the mucilage is concentrated in the center of the okra pods, chopping or slicing them releases more slime than cooking them whole.

Even if you’re not a fan of okra’s mucilage, there are still many ways to enjoy the vegetable without it. Or perhaps mucilage will go down a little easier when you remember just how useful it is, for both plants and people.

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