Why is Japan’s Food Suddenly Infested with Frogs?

Why is Japan’s Food Suddenly Infested with Frogs?

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Pictures: kikisorasido; rishiya / PIXTA(ピクスタ)
Who brought all these frogs? As the little green creatures proliferate in Japan, they're suddenly showing up in salads and udon.

Residents of Japan are struggling to contend with rising prices on everything from heating to eggs. Now, they have another problem: additional (and generally unwanted) protein showing up in their food.

The furor with frogs

Frog mens sitting on a leaf boi
Picture: 工場長 / PIXTA(ピクスタ)

The trouble appeared to start around May 11th. A supermarket in Ueda in Nagano Prefecture told customers that it had discovered a frog in one of its premade salads. They said the problem stemmed from the company in Matsumoto that made the salads for them. It appears the little green mens made its way into some of the raw ingredients to have a bite (or perhaps a snooze).

The next victim of Attack on Frog was udon chain Marugame Seimen. On May 16th, Marugame released its new product, Shake Udon, an udon/salad takeout combo. However, the launch didn’t go according to expectations. Footage of a frog swimming in the remains of udon soup swiftly made its way across Twitter, TikTok, and YouTube.

Video of a frog in a Marugame Seimen Shake Udon
Source: Twitter

On May 23rd, Marugame Seimen confirmed that a frog had found its way into at least one of its Shake Udon Spicy Tantanmen Salad products in – once again – Nagano Prefecture. The company issued a formal apology on its Web site and shut down sales of the item until it could identify and fix the root cause.

Marugame Seimen began life as a roadside stand in Hyogo Prefecture in 2000. Today, it has over 1,000 stores both in Japan and overseas.

Why all the frickin’ frogs?!

Marugame Seimen - Shake Udon
Marugame Seimen’s Shake Udon product

So what’s up with the sudden surge of frogs? Are they perhaps allying with the orcas in a final foray against mankind?

According to Kawakami Yasushi, arts and sciences director of the Tottori Prefectural Museum, it’s just that season. The tree frog proliferates in Japan from the middle of May through June. The little beasts are on the lookout during this time for any source of water in which to lay their frogspawn. That means that, anywhere you find water, you might find tadpoles.


Kawakami says he can’t say for certain how the frogs got into the food. But he assumes that they got into water outside among the vegetables or found water pools within buildings where companies process the salad ingredients after harvesting.

Another expert, Okada Jun, says that you’re bound to see more frogs this time of year as they shrug off their winter hibernation and go out in search of food. It’s likely the little creatures just get picked up when the vegetables are harvested.

Odaka says this isn’t uncommon. “It may be a shock but I’d ask people to settle down, as there’s no health risk even if one gets in your mouth.”

Try telling that to a person about to bite into a frog.

A different kind of foreign substance

Before frog terrorism, Japan had to contend with run-of-the-mill human “terrorism”. In January, visitors to conveyor belt sushi chains had a fun time filming themselves dumping various disgusting substances onto nigiri.

The “sushi terrorism” incidents sparked a national uproar. As a result, multiple chains vowed to revisit the use of the conveyor belt altogether. Several chains filed charges and police arrested multiple culprits.

No words on whether any of the frogs involved in these incidents are currently facing prosecution.

As “Sushi Terrorism” Grips Japan, Some Say Ditch the Conveyor


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Jay Allen

Jay manages the technical writing practice for ercule, an SEO, content strategy and analytics firm. A lifelong geek, wordsmith, and language fanatic, he has level N1 certification in the Japanese Language Proficiency Test (JLPT).

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