How to Choose a Ripe Durian

3. The Joint

When a durian falls from the tree, it breaks off at a weakened groove on the stem. The botanical term is “abscission layer”. The stem of a ripe durian, no matter whether it fell or was cut early, should break off at that point. You can test how close to ripe a cut durians is by wiggling the stem – if it’s loose at that point, the durian is close to ripe. If it has broken off already or comes off easily in the hand, the durian is ripe.

Mind, the stem should still be fully attached and fresh looking, with a green hue coming through the brown skin. When you scrape the stem with your thumb nail, the interior should be a grass green. If the stem is shriveled, or dark brown, the durian is days old, and chances are it was cut early and has been ripening under a tarp. It may be ripe and taste okay, but the flavor is always better from durians that fall on their own.

Some durian vendors do sneaky things like cutting the stem off at the joint and then whittling it to make it look like it fell off on it’s own. If the durian is missing it’s stem completely, or the stem looks both old and messed up, they’ll tell you it’s because the durian fell on the stem. Chances are it didn’t. Other than chewing them out for being nasty cheaters (not usually a good idea) all you can do is be aware and reject any durians that seem subpar.

4. Shake It Baby

One of the easiest ways to tell if a durian is ripe is to hold it to your ear and shake it. The flesh of a ripened durian is soft, which allows the seeds to bang around inside the shell like a maracca filled with gak.

If the seed is rattling around with no resistance, chances are the durian is overripe. If you can’t hear or feel anything at all, the durian flesh is hard. You might like it that way. No judgement.

5. Thump It

In Thailand, the preferred method is to whack the durian a few times using a rubber tipped stick. When we were given a tour of Sunshine Durian Factory, there was a team wandering about with matching green shirts, their sticks flailing. It looked so strange and out of place in a beeping, moaning forklift zone that I couldn’t help but giggle.

Most of us don’t have rubber tipped sticks, but in many other countries the side of a knife works well enough. If the durian sounds slightly hollow, it means the flesh has softened enough to recede from the shell, and the durian is at least edible. Various levels of hollowness correlate to levels of softness. Know what you like.

5. The Tooth Pick Test

I don’t think this method would go over well as a customer buying durian, but it’s run of the mill among durian sellers in Vietnam. Using a very thin, needle sharp knife, the vendor stabs the durian, piercing the shell, and then examines the knife. It’s a lot like checking on a baking cake to see if it’s ready, but opposite – a trace of goop on the knife blade means it’s ready, while a clean blade means it still needs a few days.

A lot of vendors and distributors will also lick the knife to test for sweetness, so as to assure quality control. When I first realized that probably every durian I ate in Vietnam had been pricked by a saliva-whetted knife, I kind of felt grossed out. Then I got over it.

6. Scrape It

Using the back of your nails, gently brush along the spines. It should make a rasping noise, sort of like the Mexican Scraper instrument. You can also use a stick if you don’t like the feeling of the thorns rattling your nails, in which case you have essentially turned your durian into a percussion instrument. Cool!

Once again, you’re listening for a sort of hollow reverberation that indicates some space between the seed and the shell. If only a dull clicking sound of thorns hitting the stick/your nails, don’t eat it. If it makes a low rasping noise, like one of those cool wooden frogs, the durian is probably ripe.

7. Thumb Press

This is possibly my favorite method, because it never lies. Position your thumb over one of the swollen lobes of durian so that all that separates you from the golden goodness is the half-inch or so of shell. Maneuver your thumb in between the thorns and press down. If the durian is ripe, the shell will actually give a little under pressure, like a hard sponge. If it’s not ripe, you might as well be pressing on concrete. It’s easy to tell the difference!

This technique is awesome, but may not work for all durians. Some durians have extremely thick shells that may not give at all under any kind of pressure, despite being ripe. We’re still testing it out, and will let you know the results.

Now, the bad news. None of these techniques will work on a frozen durian. Those of you buying your durians frozen from the Asian grocery will probably never find a properly ripened durian. Most likely, you have purchased a Monthong durian from Thailand, which was harvested at 80% ripeness, painted with ripening agents, allowed to sit for 3 to 5 days, and then frozen at -40 degrees celsius, destroying the cell walls. Not only was your durian not ripe when it was harvested, it has not a shred of a chance of ripening now.

Ah Durian – so sweet, so stinky, so perfectly delicious.

Got any good methods for choosing a durian? Please tell us about it by commenting below!