Kawachi issun broad bean certified as the 26th item of the “Naniwa Heirloom Vegetables”—the lineage of native varieties Osaka has kept protecting

Osaka Prefecture has newly certified the Kawachi Issun broad bean as a "Naniwa Heirloom Vegetable," bringing the number of certified items to 26 as of May 2026. It is a large-podded heirloom variety grown in southern Osaka since the Meiji era, and it met the prefecture's three requirements, including a cultivation history of over 100 years and a clear lineage. In Osaka—called the "nation's kitchen" in the Edo period—another heirloom variety handed down through the ages has been officially recognized.

What Are "Naniwa Heirloom Vegetables"?

"Naniwa Heirloom Vegetables" is a prefectural effort to unearth and protect native vegetables deeply rooted in Osaka's food culture. Certification has three requirements. First, a history of over 100 years, having been grown in Osaka roughly since before the early Showa period. Second, a clear lineage, native to Osaka or adapted to the region's climate, with seeds or seedlings available. Third, that it is still produced within the prefecture today.

It is precisely because of these strict criteria that certification carries meaning beyond a mere regional brand. Only vegetables backed by a record of who grew them, where, and with how much history behind them are permitted to bear the name.

The 26th Item: The Kawachi Issun Broad Bean

The newly certified Kawachi Issun broad bean is an heirloom variety said to originate in the Meiji era. The beans inside the pod are large and swell to a nearly round shape—a feature of the variety—with a fluffy texture and rich, sweet umami. The harvest is in May. It has been grown across several cities and towns in southern Osaka. From its plump appearance, it is also called "otafuku-mame" (lucky-faced bean).

How the Field Receives the Protection of Heirloom Varieties

Certifying heirloom vegetables carries meaning from several standpoints. For producers, adding an official backing to a native variety they have long protected is an encouragement to keep growing it. For distribution, it becomes easier to differentiate as a vegetable with a story. For consumers, it offers the experience of tasting regional food culture. As many native varieties vanished amid postwar agricultural modernization, urbanization, and the Westernization of diets, certification like this plays a role in carrying the lineage to the next generation.

Valuing heirloom vegetables is not limited to Osaka. Amid a broader move to reappraise native varieties across the country, it echoes the structure in whichinstitutional trust, like Organic JAS certification, sways consumer choice.

Impact on Readers—How to Make the Most of a Rare Heirloom Variety

For food makers and those involved in cooking, certifying an heirloom vegetable presents a new ingredient option. For a variety like the Kawachi Issun broad bean, whose harvest is limited to May, the short season is both its rarity and its difficulty. Raw, it can be distributed for only a short window, so it rarely reaches consumers far from the growing region.

Ripple Effects on the Industry—Drying Expands the Possibilities of Heirloom Vegetables

How can you deliver an heirloom vegetable that is short in season and doesn't keep well throughout the year? One answer is drying. Dried, it can be stored beyond its season and reaches consumers far from the growing region. OYAOYA, operated by Agriture, has achieved supply unswayed by season or weather by converting Kyoto's heirloom and off-grade vegetables into dried vegetables. Even a large-podded bean like the Kawachi Issun broad bean can find a path to the table past its season if drying is added to the mix.The Stability of Dried Vegetables Draws Attention Against Fresh Vegetables' Unstable Prices—the same logic applies to heirloom vegetables.

How to Enjoy It at Home

The broad bean shows its best qualities the simpler the cooking. Grilled in the pod, it steam-roasts inside and its sweetness concentrates. Boiled in salted water, you taste its fluffy texture as is. When you get a lot in season, boil and freeze them, or dry them, to enjoy past the season. The deep flavor unique to an heirloom variety comes through best when you don't overhandle it.

Summary

The Kawachi Issun broad bean has been certified as the 26th "Naniwa Heirloom Vegetable." It is significant that another heirloom variety meeting the strict requirements of a history over 100 years and a clear lineage has joined the official lineage. How to carry short-season, rare heirloom vegetables to the next generation and to the table—drying and other techniques are widening that answer.

Reference

• Osaka Prefecture "Naniwa Heirloom Vegetables"
• Osaka-mon Database, "Kawachi Issun Broad Bean"