Nationwide autumn seasonal ingredient; temple and shrine ginkgo trees of cultural significance; commercial production in Aichi and Osaka
Ginnan (銀杏, ginkgo nuts) are one of Japan's most distinctive autumn ingredients — the seed kernels of the ancient ginkgo tree, jade-green when fresh and cooked, with a uniquely rich, slightly bitter, resinous flavour that has no equivalent in Western cuisine. They are harvested in October-November when the outer fruit (highly malodorous) falls from female ginkgo trees. Processing requires protective gloves — the outer fruit contains urushiol (same compound as poison ivy) that causes skin reactions. The seeds are then boiled, their shells cracked, and the thin inner skin rubbed off to reveal the translucent green nut. Applications: chawanmushi (the classic placement of two or three ginnan in the steamed custard cup — their richness complements the egg custard); cha-kaiseki (as a tea ceremony seasonal ingredient in autumn); yakitori (skewered with rock salt); grilled in the shell until shells crack open; in dobin-mushi (autumn seafood and vegetable broth served in a small clay pot). Ginnan's distinctive character comes from ginkgolide compounds — consumed in very large quantities these cause reactions, so portions are intentionally small (three to five per serving). Their age as a species (Ginkgo biloba is a living fossil, 200+ million years old) adds cultural resonance — in Japan, ancient ginkgo trees at shrines are considered sacred.
Richly earthy, slightly bitter, resinous; jade-green colour; uniquely dense for a nut; contrasts and complements the custard richness of chawanmushi
{"Handle with protective gloves — outer fruit contains urushiol causing skin reactions","Process: boil → crack shell → rub inner skin to reveal jade-green nut","Classic applications: chawanmushi (3 per cup), cha-kaiseki autumn course, yakitori skewer","Small portions (3–5 per serving) by tradition — ginkgolide compounds present in large quantities","Grilled in shell until crack: the simplest and most aromatic preparation","Sacred tree associations at Japanese shrines — cultural resonance beyond culinary use"}
{"Microwave ginnan in their shells for 30 seconds — the shells crack open and the inner skin is easier to remove","For yakitori ginnan: skewer three or four nuts with a single skewer, season with rock salt only — the salt amplifies the resinous character","Dobin-mushi (autumn mushroom and seafood broth in clay teapot) with ginnan is the seasonal kaiseki preparation par excellence — the teapot service theatrics frame the delicacy"}
{"Handling raw outer fruit without gloves — urushiol contact causes dermatitis","Over-cooking ginnan — jade-green colour turns yellow-brown and texture becomes mealy","Serving large portions — tradition limits to 3–5 per serving for good reason"}
Tsuji, Shizuo. Japanese Cooking: A Simple Art. Kodansha, 2012.