Tampoi is not cultivated in orchards as far as I know. It is jungle produce. It is rarely in the market, and the first time I saw it I bought a few. They were sold on long woody stalks. The fruit fit easily in your hand, and they were cracked open in the same way as mangosteen, by a little pressure from the top. They split neatly into thirds, and inside the woody husk are six small orange-yellow fruits. When I bought them, I didn’t consider them terribly expensive, just a few ringgit a kilo. But when you consider each kilo only yields a few grams of edible fruit that you consume in an instant, it starts not to look like a very good deal. I couldn’t imagine wanting to buy them again; there was just nothing special about them at all except the novelty. Another rare fruit is Rambai. I only saw it for sale once, so I bought it. It closely resembles langsat and duku, but I don’t know how closely they are related botanically. They only way I can tell them apart from the outside is by the stems, which are green and soft, rather than brown and twiggy like langsat/duku. I rather like langsat; it can be tart, especially the small ones, but the sweetness has a nice flavor, and the fruit is fleshy enough to give you something to chew on and work around in your mouth. The seed is very bitter if you bite it though, which is easy to do because it is kind of soft. Langsat is reliably found in the market; I think there are two seasons. It sells for 4RM/kilo usually, which is an average price for fruit. It is worth it because you don’t pay for a lot of packaging; the rind of the langsat is thin. Langsat and duku are distinguished by one being easier to peel and the other having a milky sap when you break the rind. Which one is which though, I don’t know. My wife thinks what is called langsat here is called duku in West Malaysia. What is called Langsat here has the trickier rind to peel and the milky sap.
Rambai, or at least the rambai I got suckered into buying, is intensely sour, like sucking on a lime. I couldn’t get through the amount I bought. The flesh is maybe a bit juicier than langsat, less meaty, with a more distinct membrane around the edible part, but it’s hard to appreciate all that when your face is puckered up from the sourness. Maybe there are better ones than the ones I bought, but I doubt I’ll take the chance again, especially if there’s langsat around too. How about that cluster of fruit though, eh? Can you imagine something like that hanging off a tree? Very cool.