Growing up in the US, bamboo shoots were a food you bought in a can, and aside from a passing acknowledgement that they were related to the tall green stalks that pandas eat, I never really put much thought into how they're grown or how they're prepared. One time, I found some fresh bamboo at a Chinese market and decided to try it out.
Peeling the tough exterior sheaths to reveal the pale tan interior reminded me a bit of an artichoke, and I decided to fry them up with some olive oil, garlic, salt and pepper. Lightly caramelized around the edges and redolent of garlic they looked great, but after a few bites I realized something was not right. Although it had cooled, the bamboo felt like it was burning my esophagus going down and left me with a bad case of heartburn. Luckily I ended up throwing most of it out. I say "luckily" because it turns out bamboo contains some potent toxins that need to be neutralized before it can be eaten safely.
Like casava (aka tapioca) Lima beans, sorghum and flax seeds, bamboo naturally contains cyanogenic glycosides that break down in the gut to produce cyanide. In the case of bamboo, the compound is called taxiphyllin and although the concentrations vary by species, it's a very bad idea to eat improperly prepared bamboo. The good news is that unlike, most cyanogenic glycosides, taxiphyllin decomposes readily when heated over time, rendering it perfectly safe to eat.
In Japan, early spring is a forager's delight, as the snows melt, and a bounty of wild mountain vegetables start poking their way through the forest floor. This is around the time that Bamboo shoots, or takenoko (竹の子, literally "bamboo child") start showing up at markets and although you can get the prepared kind vacuum sealed in water year round, there's some primal satisfaction of foraging for, and preparing your own. When foraging for bamboo (like all wild vegetables) be sure you know what you're doing as there are only certain species of bamboo that are edible.
As for the preparation process, it's fairly simple. You just peel and trim them and boil them in water for two hours before soaking them in clean water overnight. In Japan nuka, or rice bran (the stuff that's milled off of brown rice), is usually added as it's said to absorb the toxins. I haven't done enough testing to be able to say for certain that it helps, but the claim sounds dubious since it's the heat and time that breaks down the toxins. Still, who am I to argue with people that have been preparing it this way for generations.
- Rice bran (optional)
- Peel the dark colored sheaths from the bamboo, starting from the bottom and working your way to the top. Trim any dark bits off the peeled shoot using a knife.
- Place the bamboo shoots in a pot and fill with enough water to cover the bamboo by a few inches. You can optionally add some rice bran (the part thats stripped off from the brown rice as it's milled).
- Bring the pot to a boil and continue boiling for 2 hours, adding water periodically to keep the bamboo covered.
- Drain and rinse off the bamboo and then store refrigerated in water for at least 1 day before using.
Andrew Mace says
2 hours. Seems excessive. I’ve eaten many times cooking it for only a couple minutes. 🤔
Marc Matsumoto says
Hi Andrew, different types of bamboo have different levels of cyanogens, so it's possible the ones you're getting are relatively low in cyanogens, or that you've built up a tolerance to them. Time and heat break down these compounds, and a couple minutes is definitely not enough to destroy them, so you're playing a risky game as these compounds convert to cyanide in the gut.
So here’s how our people do it(I’m from Nagaland). First slice it into thin pieces and wash it thoroughly. Next get some ash from burned wood and clean that to get the charcoal and other impurities out. Put the ash and bamboo shoots in water filled to the brim. Close it and keep it for a week, or at least 3-4 days. When you open it, there will be bubbles formed. Take out the bamboo shoots and clean them. Next, let the impurities in the water which you soaked the bambooshoot in settle down and use the cleaner water at the top to cook the bambooshoot in. Use dried red chillies. Cook for over an hour. After it cooks, toast some sichuan peppers, crush them and sprinkle them. Mix well.
Marc Matsumoto says
Hi Nara, it's so interesting hearing about how it's prepared in other cultures. Thanks for sharing!
Hi! I’m an American living in Japan and walked by a neighbor selling bamboo roots and little bags of rice bran....the directions given to me were a little unclear, so thank you for posting this! I hope it turns out ok....I already had an allergic reaction by eating raw, unfamiliar foods....taro! I’ve learned to do a little research first 🙂
Marc Matsumoto says
Hi Anne, good luck! Bamboo shoots need to be consumed when very fresh (ideally the day it was harvested). Since I've posted this, I've stared cooking them in a pressure cooker. It consistently gets rid of the burning sensation in the back of the throat (that I'm assuming is the toxins), in about 30 minutes without rice bran. The cyanogenic glycosides break down with temperature and time, and since a pressure cooker is able to achieve higher temperatures the toxins break down faster.
Thanks. l prepared some fresh bamboo unaware of the toxins. l did soak them for a while before cooking, though the taste was still rather bitter. I didn't have any problem though regarding digestion. But the bitterness prompted me to think l had better check into how to prepare it properly! Definitely l will try your method next time as l do love the texture.
Marc Matsumoto says
I'm glad to hear you're okay. Humans developed taste receptors for bitter compounds to warn us away from eating foods that can be toxic, so it's usually a good idea to listen to your tastebuds 😉