What is Mi-Zansho

At Hokkaido Uni Shop, our goal has always been simple: to find the very best ingredients Japan has to offer—and make them available to people around the world who truly appreciate them.

Having lived abroad for almost 30 years, I’ve come to realize just how little of Japan’s culinary richness is actually known outside the country. Honestly, I’d say maybe 30% of what Japan has to offer is recognized globally. There are so many amazing, seasonal, and deeply traditional ingredients that never leave Japan—not because they’re not in demand, but because they’re hard to export, rare, or just overlooked.

One of those hidden gems is Mi-zansho,or 実山椒 the fresh green peppercorn from the Sansho plant. And after months of navigating export rules and coordinating with farms,  twe’re finally able to offer it abroad for the first time! Even better, our first batch is already reserved by several Omakase chefs in the U.S.—and we only have a small amount left for home chefs and food lovers who want to try something really special.

So, What Exactly Is Mi-zansho?

Mi-zansho is the young green peppercorn harvested from the Sansho plant in early summer. If you’ve had powdered Sansho sprinkled on grilled eel (unagi), this is the same plant—but this version is fresh, fragrant, and tingly in a way that dry powder just can’t compare to.

It’s citrusy. It’s electric. It’s floral and bright. It’s hard to describe until you try it, but once you do, you’ll understand why it's been part of Japanese cooking and herbal medicine for centuries.

Throughout the year, different parts of the plant are harvested:

• Spring: tender leaves (kinome) and the rare flower buds (hana-zansho)
• Summer: fresh green berries (mi-zansho)—what we’re offering now
• Fall: dried outer skins ground into the familiar Sansho powder

Mi-zansho is most often used in traditional dishes like chirimen-zansho (baby sardines with peppercorn), tsukudani, and even in sansho-kombu (kelp simmered with pepper). But more recently, chefs are experimenting with it in everything from grilled meats and pasta to cocktails and desserts.

How to Prepare and Store It

Since it's only available for a short window each year, preserving it well means you can enjoy it year-round. Here’s how we do it:

• Clean – Remove the little stems by hand or with scissors.
• Rinse and drain – Give them a quick wash and dry them well.
• Freeze – Either vacuum-seal them or wrap tightly in plastic wrap with no air gaps.

Just remember: don’t thaw when you’re ready to use them. Take them out straight from the freezer and use as needed—they’ll retain their full aroma and punch.

Why This Is Such a Big Deal

To be honest, even in Japan, Mi-zansho is not easy to get. It’s harvested for just a few days a year in very small quantities. Most is used locally or by high-end restaurants.

This year, our team personally visited producers in Kyoto and Kochi Prefecture—a region known for its clean air, pristine mountain water, and incredibly aromatic Sansho. We met with several farmers, and after tasting, testing, and building trust, we were lucky enough to secure just 1kg for our first overseas batch.

That’s right. Just 1kg.

It’s our first time exporting Mi-zansho—and as far as I know, we’re the first to offer it internationally in this form. It’s a small step, but it means a lot.

Want to Try It?

If you’re curious or passionate about Japanese ingredients—or just love discovering something rare and seasonal—Mi-zansho might become your next favorite kitchen secret. Order here: Fresh Japanese Sansho Berries 500g Or feel free to email us with any questions: hokkaidounishop@gmail.com

—Tad Kumagai
Founder, Hokkaido Uni Shop

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