How to Choose Naturally Ripened Jackfruit and Avoid Chemically Ripened Ones

Jackfruit is now available in markets all year round, not just during the summer as it used to be. This abundance, while convenient, also makes it harder for consumers to know how to choose fruits that are truly ripe on the tree and free from harmful chemicals.
If you love eating jackfruit but want to make sure it’s naturally ripened, here are some useful tips to help you tell the difference.

The Hidden Danger: Jackfruit Ripened with Chemicals in Less Than 24 Hours

Jackfruit is one of the most popular tropical fruits thanks to its sweet aroma, bright color, and rich flavor. However, it also ranks among the fruits most often artificially ripened with dangerous chemicals — substances that pose serious risks to consumer health and food safety.

In the past, traditional ripening methods involved leaving the fruit to mature naturally. Farmers would let the jackfruit ripen on the tree, or use safe techniques such as sun exposure, placing it near lime or ash, or waiting several days for it to ripen on its own.

Nowadays, in the rush to meet market demand and maximize profit, many traders use chemical agents to ripen jackfruit in less than a day. They inject or brush the fruit with chemical solutions that accelerate the ripening process, making the skin turn yellow faster and the fruit appear more appealing.

These substances — often imported illegally from other countries, including China — are hazardous. When injected into unripe fruits, they can alter the natural flavor, destroy nutrients, and leave toxic residues that can harm consumers over time.

How to Choose Good and Naturally Ripened Jackfruit

1. Look at the Shape and Surface of the Fruit

Naturally ripened jackfruit usually has a slightly dull yellow skin and its spikes (or “thorns”) appear even and slightly soft. Choose fruits that have a consistent, round or oval shape without deep dents or uneven areas.
Fruits with sunken spots or uneven bulges often have internal problems — they might be worm-damaged, contain too many fibrous parts, or have dry, hard sections inside.

2. Check the Aroma

One of the easiest ways to identify naturally ripened jackfruit is by its fragrance. Ripe jackfruit emits a strong, sweet aroma that can be noticed from several meters away. If the fruit has little or no smell, it may have been chemically treated to ripen quickly.

3. Examine the Spikes (Gai)

Observe the spikes carefully: if they are wide apart, rounded at the tips, and the skin looks slightly yellow, the fruit is likely ripe and ready to eat. When you tap it, it should make a hollow “thud” sound.
In contrast, jackfruit that’s still green or chemically ripened tends to have sharp, closely spaced spikes. The surface feels hard to the touch, and tapping it produces a dull, solid sound instead of a light echo.

4. Look at the Sap (Latex)

When you cut open naturally ripened jackfruit, you’ll notice very little sticky sap. The sap is light yellowish or cream-colored and flows slowly.
However, if the fruit was forced to ripen with chemicals, the sap tends to be thick, milky white, and abundant — sometimes even dripping out as soon as the fruit is opened.

How to Tell Thai Jackfruit Apart from Vietnamese Jackfruit (Mit Nghe)

According to an expert from the Southern Fruit Research Institute, there are currently six to seven popular Thai jackfruit varieties grown in Vietnam. In appearance, Thai jackfruit is generally shorter and more rounded, while Vietnamese “mit nghe” tends to be longer in shape.

The outer color also differs slightly: Thai jackfruit is bright yellow, whereas Vietnamese varieties have a greenish-yellow skin. The flesh of both is golden, but in taste, Vietnamese jackfruit is often considered superior — it has a naturally sweet, slightly floral flavor, while Thai jackfruit tends to be sweeter but less aromatic.

Additional Tips for Buyers

• Avoid fruits that look too perfect: If the color is uniformly bright and the smell is faint, it might have been treated with chemicals.

• Buy from trusted vendors: Choose sellers who can tell you where the fruit was grown and when it was harvested.

• Observe the stem: A natural jackfruit stem turns dry and brown as it ripens, while chemically ripened ones often have fresh-looking stems despite their yellow skin.

By paying attention to these small details, you can enjoy delicious, naturally ripened jackfruit safely — and protect your family from harmful substances hiding behind a seemingly perfect piece of fruit.