Ginkgo the Great

You might know this tree by its lovely fan-shaped leaves, or by its awful smell. Every year, toward the end of November the (female) Ginkgo biloba omits a stench that lasts for weeks. This foul odor — a cross between pungent cheese and vinegar (or poop, your call) — occurs when the Ginkgo fruits start to ripen. Inside each smelly little fruit is the ginkgo nut or ginnan as it’s called in Japan. Eaten steamed or roasted like edamame, ginkgo nuts are regarded as a delicacy in Asian cuisines.

The harvest season for ginkgo is autumn, when the leaves turn a golden saffron colour and the fruits (similar to a small apricot) begin to fall. A local ginnan picker informs me that it’s a welcome bonus when people walk on them and squish the little fruits, thus removing the outer flesh and releasing the nut.

The street I live on is lined with Ginkgo trees, and every year I plug my nose from the smell, and every year I see my Japanese and Chinese neighbours stopping to pick up these otherwise wasted fruits.

“The nuts are seen as pearls given to a dear guest” – Onhang Xiu

In North America the Ginkgo tree is planted for its aesthetic appeal and for its durability. As a botanical species, the Ginkgo is quite remarkable; botanist David Crane has concluded that it is in fact, a living fossil — “a single species with no known living relatives […] essentially unchanged for more than 200 million years.” There are “only five living groups of seed plants (in the plant kingdom) and ginkgo is one of them” says Crane. “The ginkgo is solitary and unique,” Crane continues, and “not very obviously related to any living plant.” According to research fossils dating back more than 200 million years, this beauty of a tree is here to stay (source). The tenacity of this plant is perhaps best encapsulated by the fact that after Hiroshima the Ginkgo was one of the only living things to survive (source).

This year I decided I was going to finally ask about this curious yet offensively scented tree. The ladies I spoke with were more than happy to share their knowledge of the ginkgo tree with me. “Where I grew up (in rural Japan) everyone had a ginnan tree” said one woman. “We ate them all the time” she says, “but here no one eats them and they are everywhere!”

The Chinese use ginkgo nuts in congees and they are served on the Chinese New Year, while the Japanese use them in a dish called chawanmushi (steamed egg custard). Roasting or steaming, however, is the most common way to prepare and enjoy ginkgo nuts.

How to Prepare Hand Picked Ginkgo Nuts:

Steamed method:

Steamed Ginko nuts

Thoroughly wash the ginkgo seeds until all of the outer flesh is removed.

Once all of the skin has been removed from the nuts, lay them out to air dry for 2-3 days (though other sources say as few as 6 hours will do).

When the nuts are dry, simply steam the nuts for 5 minutes or until the hard shells start to crack open (when cooked the ginkgo nuts will turn a bright green like edamame beans).

Remove and discard the shells

Sprinkle with coarse salt and enjoy.

Pan Fried Method:

Put washed and dried ginkgo nuts into a frying pan over medium-high heat with 1 tablespoon of oil.

Heat for 2-3 minutes (or until the shells start to pop open).

Remove the nuts and discard shells.

Sprinkle with salt and enjoy.

HEALTH WARNING

Those with allergies to cashews or mangoes should not eat ginkgo nuts. The Ginkgo can also cause a slight stomachache when overindulged.

Wikipedia states that “when eaten in large quantities or over a long period, especially by children the gametophyte (meat) of the seed can cause poisoning by [4’-O-methylpyridoxine] (MPN).” Sources say children under 10 should eat no more than 5 ginkgo nuts per day and adults no more than 10. (Though, my neighbour friend says maximum 40 a day, but I’m willing to bet she’s built up a tolerance).

The ginkgo fruits also contain an allergen similar to poison ivy that may irritate the skin and cause a mild rash in some individuals. As such, anyone harvesting ginkgo fruit should wear rubber gloves.

Sounds a bit scary right? So why eat do people eat them? Because they are delicious and nutritious! Or, so I am told (I’m still getting past the smell). The flavour is described as slightly bitter-sweet and the texture like a chestnut.

While much of today’s research is of the Ginkgo leaves and their medicinal properties, the Gingko nuts too are rich in protein, beta-carotene (290µg/100g), Vitamin C (23mg), iron (1.0mg), magnesium (53mg), phosphorus (120mg), and potassium (700mg).

I tried to locate commercial ginkgo nuts but had no luck finding any for sale. When available, they are usually found frozen or canned and sold in Asian markets.

Her
e is a plethora of recipes with Ginkgo nuts to get you started:

Nagaimo no ebi-iri kinchuakuni /Chinese yam with prawns in thin deep-fried tofu packets, simmered in broth

Ginnan gohan /gingko nut rice

Oden/fishcake, tofu and daikon radish stew

Ebi to ginnan-iri mushi-renkon manju / steamed lotus root dumplings with prawns and gingko nuts

Kaisen chukadon/Chinese-style seafood saute over steamed rice

Atsuage no guriru, yasai ankake/grilled deep-fried tofu with thickened vegetable sauce

Sansai gohan/rice with mountain vegetables

Ebi to yurine-iri ganmodoki/deep-fried tofu patties with prawns and lily bulbs

Kayaku gohan/steamed rice with assorted ingredients

Ganmodoki/deep-fried tofu patties

Photos (steamed ginkgo, skewers and the yellow leaves) were used from Japan Food Style.