Mangosteens are mildly acidic. UC Davis postharvest experts report that ripe mangosteen flesh has a pH of about 4.5 to 5.0, with titratable acidity of 0.7% to 0.8% and soluble solids (mostly sugar) of 17% to 20% (Kader, UC Davis). That pH is in the same gentle range as bananas and lychees. But mangosteens carry more total acid than most other Southeast Asian fruits, which is why the “queen of fruits” tastes sweet with a noticeable, refreshing tang.

If you have acid reflux or sensitive teeth, mangosteens are usually a reasonable choice in moderate amounts. This guide explains how acidic mangosteens really are, how they compare with lychees, rambutans, and longans, what canned mangosteens mean for your diet, and how to enjoy them.

Key Takeaways

• Mangosteens are mildly acidic, with a pH of about 4.5 to 5.0 per UC Davis.
• They carry more total acid than their sweet cousins, about 0.7% to 0.8%, similar to a tart apple.
• They’re also very sweet, with 17% to 20% soluble solids, which balances the tang.
• Acidity drops as mangosteens ripen and during storage.
• For most people with acid reflux, ripe mangosteens are a reasonable fruit in moderate portions.
• Canned mangosteens come in syrup, which adds sugar and cuts vitamin C.

Are Mangosteens Acidic? The Short Answer

Yes, mildly. Anything below pH 7 is acidic, and mangosteens sit at about pH 4.5 to 5.0. The FDA’s widely used pH table doesn’t list mangosteen (FDA), so here’s what other sources report:

Values vary with cultivar, ripeness, and storage time.

So mangosteens have a mild pH, but a moderate amount of total acid. Both numbers matter, and we’ll explain why next.

Why Are Mangosteens Acidic and Sweet at the Same Time?

pH and total acid measure two different things:

• pH tells you how strong the acidity is in the fruit’s juice. Lower numbers mean stronger acidity.
• Titratable acidity tells you how much acid the fruit contains overall.

Mangosteens have a mild pH (4.5 to 5.0) but more total acid (0.7% to 0.8%) than many similar fruits. Fruits contain natural buffers that keep pH from dropping as much as the total acid might suggest. Mangosteens also have a lot of sugar, 17% to 20% soluble solids (Kader, UC Davis). The result is a fruit that tastes sweet first, with a bright, tangy finish.

We couldn’t find a published breakdown of which organic acids dominate in mangosteen flesh.

How Acidic Are Mangosteens Compared With Apples?

Here’s how mangosteen’s total acid compares with some fruits we’ve covered:

Different studies and methods; use as a general comparison.

Mangosteens carry about as much total acid as a tart Granny Smith apple, more than rambutans, and far less than passion fruit. But mangosteen’s pH (4.5 to 5.0) is milder than an eating apple’s (3.30 to 4.00 per the FDA).

Do Mangosteens Get Less Acidic as They Ripen?

Yes, overall. A Thai study following mangosteens through maturation found that titratable acidity rose early in development, then decreased until full maturity, while soluble solids in the aril kept increasing (Ratanamarno et al., 1999).

Acidity also falls during storage. In an Indonesian study, total titratable acid was about 0.60% to 0.74% right after harvest and dropped to about 0.14% to 0.20% after 30 days of storage (Sumiasih et al., 2019).

What this means: Fully ripe mangosteens taste sweeter and less tangy than underripe ones.

Are Mangosteens More Acidic Than Lychees and Rambutans?

Mangosteens are often grouped with lychees, rambutans, and longans as Southeast Asian specialty fruits. Here’s how their acidity compares:

Sources: mangosteen and longan from UC Davis (mangosteen, longan); rambutan from Chai et al., 2018 and UC Davis; lychee pH from the FDA.

The takeaway:

• By pH, mangosteens, rambutans, and lychees are about the same. All three sit around pH 4.5 to 5.
• By total acid, mangosteens are the tangiest of the group. That’s why they have a more noticeable sweet-tart flavor than lychees or rambutans.
• Longans are the least acidic, close to neutral.

How Acidic Are Mangosteens Compared to Other Fruits?

Here’s where mangosteens fall next to other fruits in the FDA’s pH table (FDA):

Source: FDA, Approximate pH of Foods and Food Products; mangosteen and longan from UC Davis; passion fruit and guava from published studies.

A few takeaways:

• Mangosteens are less acidic by pH than citrus and tangy tropical fruits like pineapple, mangoes, guava, starfruit, and passion fruit.
• They sit alongside low-acid fruits like bananas, persimmons, and dragon fruit.
• Papaya, longans, and melons like cantaloupe are even milder.

For the full list, see our complete guide to acidic foods.

Are Canned Mangosteens Acidic?

Fresh mangosteens can be expensive and hard to find, so many people buy them canned. We couldn’t find a published pH for canned mangosteens, and the FDA table doesn’t list them. USDA’s only mangosteen entry is canned in syrup (USDA FDC 169090):

Source: USDA FDC 169090. USDA doesn’t currently list fresh mangosteen.

What this means:

• Syrup adds sugar and calories. Drain canned mangosteens and rinse off the syrup if you’re watching sugar.
• Vitamin C is low. Canned mangosteens have only about 2.9 mg per 100 g.
• Check the label for added acid. Some canned fruits include citric acid, which can add tang.

Are Mangosteens Too Acidic for Acid Reflux?

For most people, no. Mangosteens aren’t on the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) list of foods that may worsen reflux, which includes citrus fruits, tomatoes, alcohol, chocolate, coffee and caffeine, high-fat foods, mint, and spicy foods (NIDDK). Their pH is mild and they’re very low in fat.

That said, mangosteens carry more total acid than lychees or longans, so very sensitive people may notice them more. The American College of Gastroenterology’s 2022 guideline recommends that people with GERD identify their own triggers and avoid eating within 2 to 3 hours of bedtime (Katz et al., 2022).

Tips for Eating Mangosteens With Reflux

1. Choose fully ripe fruit. Acidity drops as mangosteens ripen.
2. Start with a few segments and see how you feel.
3. Pair them with gentle foods, like oatmeal, Greek yogurt, coconut yogurt, or cottage cheese.
4. If they bother you, swap in a milder fruit like longan, banana, or papaya.
5. Eat them earlier in the day. NIDDK suggests eating meals at least 3 hours before lying down if you have nighttime symptoms (NIDDK).

For more guidance, see our list of foods to avoid with GERD. If you have heartburn more than twice a week, trouble swallowing, or symptoms that don’t improve, talk with your doctor.

Mangosteens, Teeth, and Gastritis

Teeth: Mangosteens are mildly acidic and quite sweet. The American Dental Association recommends eating acidic foods as part of a meal, rinsing with water or having milk or cheese afterward, and waiting about an hour before brushing (American Dental Association). Our article on whether apples are good for your teeth covers similar questions.

Gastritis: Mild fruits are usually easier to tolerate with gastritis. Try a small amount of ripe mangosteen with food, or choose an even milder fruit like longan or banana. Our 7-day meal plan for gastritis has more gentle meal ideas.

Mangosteen Nutrition

USDA FoodData Central doesn’t currently include fresh mangosteen, only canned mangosteen in syrup (see the table above). Here’s what we know:

• Sugar: Fresh mangosteen flesh contains 17% to 20% soluble solids, mostly sugar (Kader, UC Davis). If you’re managing blood sugar, keep portions moderate. Our guide on whether apples are good for diabetics covers how to think about fruit and blood sugar.
• Fiber: Canned mangosteen has 1.8 g of fiber per 100 g (USDA FDC 169090).
• Folate: Canned mangosteen provides 31 mcg of folate per 100 g.
• Fresh vitamin C: We couldn’t find a reliable USDA value for fresh mangosteen.

A note on mangosteen supplements and juices: Mangosteen is also sold as concentrated juice blends, powders, and supplements. These products aren’t the same as eating the fresh fruit, and this article doesn’t cover their safety or effects. Talk with your doctor before using them, especially if you take medications.

How to Pick and Store Mangosteens

• Storage: UC Davis recommends storing mangosteens at about 13°C (56°F), with a storage potential of 2 to 4 weeks, depending on cultivar and ripeness (Kader, UC Davis).
• Ripeness: In an Australian study, eating quality was acceptable at a uniform pink skin color and best at a dark red-purple skin color (Brown et al., 1991).

Acid-Smart Ways to Enjoy Mangosteens

To open a mangosteen, gently press or score around the middle of the thick purple rind, twist it open, and lift out the white segments. Here are a few ideas:

• Smoothies: Blend ripe mangosteen segments (seeds removed) into our fruit yogurt shake with banana to soften the tang.
• Creamy desserts: Serve them with our whipped ricotta with mixed berries or a scoop of ginger ice cream.
• Breakfast bowls: Top yogurt with mangosteen segments and our pumpkin pie spice granola.
• Summer rolls: Add a few segments to our avocado summer rolls.
• Treats: Chop mangosteen into our tropical dream rice krispie treats.

The mangosteen swaps haven’t been tested in our kitchen, so adjust to taste.

Kitchen tip: The purple rind juice can stain hands and clothing, so open mangosteens over a plate or cutting board.

Frequently Asked Questions

Are mangosteens acidic or alkaline?

Mangosteens are mildly acidic. UC Davis reports a pH of about 4.5 to 5.0, with total acidity of 0.7% to 0.8%.

Are mangosteens good for acid reflux?

For most people, yes in moderate amounts. They have a mild pH, very little fat, and aren’t on NIDDK’s list of common reflux triggers. Choose ripe fruit and pair it with gentle foods.

Are mangosteens more acidic than lychees?

By pH, they’re about the same: mangosteen is 4.5 to 5.0 and lychee is 4.70 to 5.01. But mangosteens carry more total acid, which is why they taste tangier.

Why do mangosteens taste tangy?

They contain about 0.7% to 0.8% total acid, similar to a tart apple. Their high sugar content (17% to 20% soluble solids) balances that tang, giving them a sweet-tart flavor.

Do mangosteens get sweeter as they ripen?

Yes. Research shows soluble solids increase and acidity decreases as mangosteens mature, and acidity keeps falling during storage.

How do you open a mangosteen?

Gently press or score around the middle of the thick rind, twist the halves apart, and lift out the white segments. Remove any seeds before eating.

The Bottom Line: Are Mangosteens Acidic?

Mangosteens are mildly acidic, with a pH of about 4.5 to 5.0. They carry more total acid (0.7% to 0.8%) than lychees, rambutans, or longans, but their high sugar content gives them a balanced, sweet-tart flavor. Acidity drops as they ripen.

For most people with acid reflux, sensitive teeth, or a touchy stomach, ripe mangosteens are a reasonable choice in moderate portions. If they bother you, longans, bananas, or papaya are even gentler options.

Keep exploring with Are Rambutans Acidic?, Are Lychees Acidic?, Are Longans Acidic?, or our complete guide to acidic foods.

Medical disclaimer: This article is for general information only and isn’t a substitute for professional medical advice. If you have frequent heartburn, GERD, diabetes, or take medications and are considering mangosteen supplements, talk with your doctor or a registered dietitian.

References

1. Kader AA. Mangosteen: Recommendations for Maintaining Postharvest Quality. UC Davis Postharvest Center.
2. Sumiasih IH, Poerwanto R, Efendi D (2019). Study of several stages of maturity and storage temperature on color changes and shelf life of mangosteen. Int J Applied Biology 3(1). Link
3. Ratanamarno S, Uthaibutra J, Saengnil K (1999). Towards some quality attributes of mangosteen fruit during maturation. Songklanakarin J Sci Technol 21(1):9–15. AGRIS
4. Brown BI, Wong LS, Wells IA (1991). Postharvest Ripening and Packaging of Mangosteen. QDPI Horticulture Postharvest Group.
5. USDA FoodData Central. Mangosteen, canned, syrup pack (FDC 169090).
6. Chai KF, et al. (2018). Sains Malaysiana 47(7):1483–1490. Link
7. Kader AA. UC Davis fact sheets: Rambutan and Longan.
8. Dantas AMT, et al. (2018). Bioscience Journal 34(6). DOAJ
9. Good Fruit Grower. How to measure Honeycrisp qualities.
10. U.S. FDA. Approximate pH of Foods and Food Products.
11. NIDDK. Eating, Diet & Nutrition for GER & GERD.
12. Katz PO, et al. (2022). ACG Clinical Guideline for GERD. doi:10.14309/ajg.0000000000001538
13. American Dental Association. Dietary Acids and Your Teeth.