The name of rambutan in English and Spanish is the same. For slang, it’s often called the hairy fruit.
Coincidentally where it’s native – Indonesia and Malaysia – the meaning in the Malay language is the same thing; the word “rambut” translated to English is “hairy.”
Though rest assured, you are not eating its so-called hair. What’s underneath that spiky skin is the part you eat.
What is a rambutan?
This fruit is related to the lychee and longan but is a distinctly different species. The rambutan, whose scientific name is Nephelium lappaceum, grows in Southeast Asia on a tall evergreen tree. Only the female and hermaphroditic trees produce this single-seeded berry, which is encased in a red or yellow rind coated in hair-like tentacles.
The pronunciation is ramb-boot-en and even if you say that correctly, chances are the guy in your produce department won’t have a clue what you are talking about.
In a major Chinese city or the countries of Costa Rica, Mexico, and Ecuador you may get a different reaction, but in the USA and Canada, it’s a total novelty fruit.
What does a rambutan taste like?
You don’t eat the fibrous rind. Once peeled, a white fruit about the size of a ping pong ball will be revealed. Gushing with juice, the flavor of the rambutan is a very subtle almond-like taste. With an equal ratio of fructose and glucose, the sweetness of its flesh is significant. The texture is gelatinous.
When you compare the flavors of rambutan vs. lychee vs. longan, there’s not a lot of difference. Likewise for their nutritional facts and benefits, which we will discuss in a moment. They’re all part of the same plant family which is Sapindaceae, also known as the soapberry family.
How to eat a rambutan
1. Choose a ripe rambutan
When ripe, the most common variety of rambutan will look bright red with green spines or hairs. If those have turned partially black then the fruit is passed its prime, yet still edible.
With some varieties, the skin turns orange or yellow when ripe instead of red. All are green prior to ripening, so you never want to eat a green one.
2. Cut a slit around its circumference
Place the fruit on a cutting board and cut deep enough to go through the tough rind. You can’t cut the fruit in half because in the center is a large seed.
Rather than trace the knife around the circumference, it’s often easier to hold the knife stationary and slowly rotate the fruit like you would a dial, using your thumb and index finger. Do this until the cut goes all the way around.
3. Squeeze the rind off one hemisphere
After cutting the circumference, you can easily squeeze off one-half of the rind using your fingers.
4. Peel rind off remaining hemisphere
Depending on its ripeness, the last half can also be squeezed off. Though if you want to minimize juice loss, peeling the rind will put less pressure on the fruit.
5. Remove seed before eating
Underneath the bright white pulp is a large seed which is not edible. It contains saponins and tannins which are poisonous.
With the “freestone” type of rambutans, you can easily slide the seed out using just your fingers. With the “clingstone” type, you have to manually peel or cut the seed fragments off the flesh. The latter is messy and will leave behind a paper-like substance stuck to the fruit, which requires further removal.
To make this last step simpler, you can also leave the seed inside and eat the juicy flesh as you would an apple, albeit a small one. That’s how they’re often consumed in Indonesia and elsewhere.
Uses and recipes
Preparing the fruit may sound like a hassle – and it is – but once you get the hang of it, you can get them ready in no time at all.
What is rambutan good for? Here are some uses for them in recipes:
- Add to sweet curries in place of pineapple.
- Include in a tropical fruit salad.
- Fresh rambutan juice is a popular drink, canned or fresh.
- Mixed drinks use it as a flavoring and garnish.
- Australia is known for making rambutan wine.
- Sweeten and flavor protein shake with the blended fruit.
- Dice into chunks for topping ice cream.
- Top breakfast foods like cereal, oatmeal, and pancakes.
- Puree for exotic flavor boost in homemade cheesecake.
- The hollowed rinds can be stuffed for hors d’oeuvres.
- Eat plain as a whole food dessert.
Where to buy rambutan?
Unlike a tomato, which can be picked green in Mexico and two weeks later, end up red on a store shelf in Michigan, this is a fruit that only ripens on the tree. You can’t prematurely harvest it. This is one of the reasons why it’s so hard to find for sale in the United States, United Kingdom, Canada, and other countries where it only has a niche following.
Given the low demand and awareness of this fruit, it’s just not economical to expeditiously ship it from the tropical climates of Central and South America.
The rambutan season in the USA is late June to August and again in December through January, as the trees flower and produce a crop twice yearly. Since even 50° F is too cold for it, the US crop primarily comes from Hawaii. Less commonly, it’s grown in greenhouses and the southernmost portions of Florida and California.
The fruit has been spotted for sale at select locations of the following:
- Trader Joe’s
- Whole Foods Market
- Sprouts Farmers Market
- 99 Ranch Market
- Lazy Acres Market
- Independent Asian supermarkets
That’s according the Specialty Produce app, available on iTunes and Google Play.
Walmart… so you can buy them everywhere?
The big catch is that with any of these chains, rarely have they been seen for sale and it’s only at select locations. For example with Whole Foods, there’s only one reporting from nearly a year ago at their Santa Rosa store.
Of course the sample size of reportings is small but here in Los Angeles, we haven’t seen them at Whole Foods before. Even in major cities like LA, Miami, and NYC, there’s just no guarantee you fill be able to buy them.
One place you will be able to buy them is on Amazon. Yes that’s right, you can order fresh rambutans online that have been imported from Guatemala in a 5 lb shipment. Alternately, a brand you may recognize, Melissa’s, offers them in a smaller 2 lb shipment.
- 40% of daily value for vitamin C per 100g serving
- 11% for dietary fiber
- 10% for the mineral manganese
- Reasonable impact on blood sugar
- High amounts of antioxidants in the peel
- Peels contains geraniin, a potential anti-hyperglycemic agent.
- Fatty acid synthase (FAS) inhibitors from peel being researched for cancer and obesity benefits.
- Anti-aging effects from phenolic extracts of peel seen in rodent study.
- Discarded peels from canned rambutan may be useful for making antibacterial cleaning agents.
- Fatty acid profile of seed comparable to cocoa butter and offers potential for cosmetics.
- Seed extract demonstrated inhibitory effects against herpes simplex virus in lab study.
- Trypsin inhibitor in seed demonstrated some anti-tumor and antiviral activity against HIV in lab.
- Seed kernel fat may be good carrier for fat-soluble nutraceuticals.
Sources: (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13)
With the exception of the basic nutrition facts for content of vitamins, minerals, and fiber, there are no rambutan medicinal uses which have been proven.
As you see, virtually all of the research revolves around the parts of the plant you don’t eat – the tough rind/peel and the nut-like core. Furthermore, those health benefits being studied involve specific isolated compounds from them. That’s far different from the whole peels or seeds!
Can you eat rambutan seeds raw?
No, both the seeds and the peels contain nephelium saponins and tannins. Their advantage is that they may be antibacterial, antiviral, and anti-parasitic according to research. The disadvantage is that they have those qualities because they are poisons! Eating the raw seeds or skins will cause stomach aches, vomiting, diarrhea and possibly more severe side effects.
A search of medical literature on PubMed.gov did not produce any case studies of overdosing or these parts killing people. Though the possibility of death from eating too much of them is certainly within the realm of possibility.
Cooking, boiling, and roasting will cause some of the toxins to degrade but that doesn’t necessarily make them safe to eat.
In a study with mice, the extract of roasted rambutan seeds didn’t noticeably affect them, but other forms produced narcotic-like effects:
“The locomotor activity was significantly reduced in mice treated with raw and boiled methanol seed extracts.”
This adverse reaction was observed in a dose-dependent manner. (14)
Now it is true that some people eat the roasted seeds in the Philippines and elsewhere, but that seems like playing with fire. If the poisons are not 100% destroyed during the roasting process, then that part of the rambutan would still be bad for you. Even if it’s not producing noticeable side effects.
The truth about antioxidant content
With the exception of rutin (found in apples), kaempferol, and quercetin, the most common antioxidants in plants are colored. This is why most white fruits and veggies rank extremely low on the ORAC scale, which is a measure of antioxidant content.
Fresh rambutan only have an ORAC value of 140. If you compare to its cousin the lychee, 540 is their value. 300% higher but it’s still quite low.
When you compare equal weights of those and apples, the latter has an ORAC of 3,049 (an average across all common varieties). Apples have over 2,000% more antioxidants than what rambutan have!
As one would expect, the vast majority of the rambutan’s antioxidants are found in the bright red peels; gallic acid, caffeic acid, syringic acid, and p-coumaric. Unfortunately these beneficial compounds are intertwined with toxins, so can’t view them as dietary source. (15)
Is rambutan good for pregnancy?
With the exception of C, it has low vitamin content. It’s not a source of folate (vitamin B9) which is important during pregnancy for reducing the risk of neural tube defects in babies. While there are no known reasons why rambutan fruit would be bad for you during pregnancy, the same can be said about it being good – there’s no scientific evidence of it offering unique advantages.
Consider better pregnancy superfoods.
Is rambutan good for diabetics?
Many herbal remedy websites are perpetuating a myth that rambutan kills or destroys diabetes. That disease is not caused by bacteria or a virus so you can’t literally “kill” it but that’s the actual verbiage they’re using.
The myth that it’s good for diabetes stems from the geraniin compound found in the peel. Preliminary lab research suggested it might have a blood sugar lowering effect. That was using isolated geraniin injections in animals, not humans. When consumed orally, it has “limited gastrointestinal absorption” and even when it’s in the bloodstream via injection, it’s not proven to lower blood sugar. (16)
Plus, there are higher amounts of geraniin in the plant it’s named after… geraniums. (17)
Aside from that, the good news is that the glycemic impact of fresh rambutan should be reasonable. Not great, but likely better than many other tropical fruits, as those are notorious for being diabetic disasters.
This hypothesis is based on the glycemic index of lychees, which have an almost identical composition. A 100g serving (3.5 ounces) of the fresh was found to have a GI of 57, which is considered moderate. (18)
Fresh rambutan have not been tested so no one can say for sure, but the GI for the canned version has been measured. A serving of 120g (4.2 ounces) had a high GI of 79. However that’s not a good comparison to the fresh. The canned ingredients typically include sweetened syrup added and the serving size in this study was 20% larger than the fresh lychee study. (19)
Is rambutan good for you? The amount of calories per serving is comparable to other fruits and so is the sugar content. As a snack or side dish it’s arguably better for you than mango, watermelon, and similar fruits that have a higher glycemic impact. With the exception of vitamin C and manganese, the content of vitamins and minerals is trivial.
The side effects of eating too much rambutan will be an unhealthy blood sugar spike and that goes for both diabetics and healthy individuals.
Given these nutrition facts and its very low antioxidant content, the best conclusion would be that rambutan is average for health. You certainly can’t call it a superfood.
That being said, it can still have a place in your diet. Especially here in the United States, where the novelty factor of it works wonders at house parties, or to simply give your family the experience of a new and exotic food.