Japan-wide — indigenous spice, cultivation concentrated in Wakayama and Hyogo prefectures
Sanshō (Japanese prickly ash, Zanthoxylum piperitum) is Japan's indigenous spice — distinctly different from black pepper or Sichuan pepper despite botanical kinship. Its flavour profile: initial citrus-pine-grass aromatics followed by a pronounced numbing/tingling sensation (citrus-scented numbing rather than Sichuan pepper's deep anesthetic effect) and a lingering gentle heat. Used in three forms: whole dried berries (sieved, then ground into kona-sanshō powder for seasoning), whole green berries (packed in salt for yakitori accompaniment), and kinome (fresh young leaves in spring — intensely aromatic, used as a garnish tapping between palms to release aromatics). Sanshō powder (kona-sanshō) is an essential condiment for unagi (eel), yakitori, and some noodle dishes; kinome is kaiseki's quintessential spring garnish.
Citrus-pine-grass aromatics with distinctive numbing sensation; kinome fresh leaves: intensely perfumed, ephemeral spring character; kona-sanshō: dried, concentrated, with warm numbing aftertaste
Kinome must be tapped between palms before use (this releases volatile oils trapped in the leaf cells — untapped kinome has minimal aroma); kona-sanshō is used in tiny quantities — it is intensely potent; fresh kinome season is only 2–3 weeks in early spring (it is among Japan's most fleeting shun ingredients); the numbing effect of sanshō is actually desirable and intentional — it creates a specific sensory experience that enhances following flavours.
Sanshō-crusted unagi is the classic pairing: the citrus-numbing quality of sanshō cuts through eel's fattiness and creates a flavour bridge with the sweet-soy kabayaki sauce; kinome miso (kinome leaves pounded with white miso and a small amount of mirin) is a spring condiment for bamboo shoots, tofu, and grilled fish; the numbing sensation from sanshō is caused by alkylamides — the same compounds (different type) as in Sichuan pepper — this makes the tongue temporarily more sensitive to subsequent flavours, which is why it's used on rich, fatty unagi.
Using too much kona-sanshō (it overwhelms rather than enhances); substituting Sichuan pepper for sanshō (related botanically but completely different flavour profile — Sichuan pepper is more numbing-earthy; sanshō is more citrus-floral); failing to tap kinome before garnishing (crisp green leaves with no aroma add nothing); storing kona-sanshō in unsealed containers (loses aromatic volatiles rapidly — store airtight, refrigerated).
Japanese Cooking: A Simple Art — Shizuo Tsuji