It’s not every day that you hear of a dish whose ingredients include a chemical element.

When most people hear of cesium, they probably think of either high school chemistry class or, if you happened to be glued to the TV during last year’s nuclear disaster in Fukushima, the element’s association with radiation…

So when a restaurant in central Tokyo openly advertising a lunch-time curry featuring a “cesium burger” came to our attention, we had to check it out.

Our brave food reporter Kuzo headed into town to find out whether the rumours were true and, if they were, to see what on earth a meal featuring a potentially hazardous chemical substance could taste like…

Here in Japan, hanbaagu (hamburg) and hanbaagaa (hamburger) are two very different things. While most westerners would refer to a hamburger as such regardless of whether the patty is sandwiched between buns or not, in Japan the two are treated quite differently, and have different names to indicate as much.

In places like McDonald’s, for example, you eat a hanbaagaa, i.e. a meat patty between two buns. If you’re sitting down to, say, a Japanese curry or rokomoko that contains a hamburger steak, however, you’re eating hanbaagu, which is a patty without buns. For the purposes of this article, we’ll be referring to the latter.

When I first arrived in Japan I had no idea that a beef patty minus its buns could be quite so popular. It’s surprising just how versatile a circle of ground beef can be, with many family restaurants in Japan offering page after page of hanbaagu dishes with various toppings and sauces.

▼The beef patty menu from Big Boy Japan

Feeling hungry yet? How about that cesium burger? 

“As I approached the shop and saw the sign, I saw that, sure enough, they were advertising that their hamburger steak as ‘containing cesium’,” recalls our foodie Kuzo.

The little shop, going by the name of AIUEO (from the Japanese syllabary, not unlike “AEIOU” in English), had recently launched a “Disaster recovery hamburger steak” and “Disaster recovery hamburger curry rice” dish, and was offering both for just 650 yen each (US$8). Both dishes contain hamburger patties made from beef raised in Iwate prefecture, north of Sendai, which was severely affected by the 2011 earthquake and tsunami. Like other meat and produce produced in the region post-Fukushima, the beef is reported to contain traces of the chemical.

AIUEO in Tokyo

The owner of the little restaurant, told our reporter that the two dishes were both very popular, and was happy to say that she often sold out of both. But why on earth advertise the fact that the dishes contain cesium? Was this just some bizarre way of drumming up custom?

The proprietor of the restaurant explained why she listed the chemical as an ingredient in the food:

“The beef patties really do contain traces of cesium. Since the amount of the substance in the meat is well below the ‘safe’ amount determined by the government, we technically don’t have to mention that there’s any in there. But the supplier of the patties felt that saying nothing just because the law dictates we don’t have to wasn’t right, so, even though they’re perfectly safe to eat, we decided to make it plain- these hamburgers contain cesium.”

▼”Recovery hamburger: made from Iwate beef, contains cesium: 650 yen”

If you’re sitting there open-mouthed (and not with hunger!) then don’t worry; you’re not on your own. Does this kind of thing happen often!?

Our reporter explains that food suppliers with this degree of frankness concerning what’s in their products are indeed rare, but recalls reading a news story just recently in which a similar supplier faced tough criticism after marking the contents of his food as containing traces of cesium. Stating that “we can’t say that the chemical element is not present”, the manufacturer took the extra step of adding labels to his meat that minute traces of the cesium may be present.

It’s scary to think that we may not normally know exactly what’s in the food we eat, and this is without a doubt a strange move for a restaurant to make, but we have to admire AIUEO’s frankness. Perhaps with a few more free spirits like these, we may gradually become a little bit more aware of what we’re putting into our bodies and take the power out of the hands of our respective governments.

“No doubt many people, having heard that their food is not entirely ‘clean’ would be put off, but just because it’s not normally stated so plainly doesn’t mean that a small (but safe) amount of things like cesium aren’t present in the food we consume each day,” Kuzo rationalised before settling in to try the reviving curry hamburger dish.

So how was it? Did our man struggle to get through the meal after reading its questionable ingredients? Not at all:

“It had a real home-cooked taste to it; soft, juicy and so very welcoming. A genuinely heart-warming dish.”


Menu image (C) Big Boy Japan
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