Steven Stern, a former fact checker and a full time food fiend, is here to complicate things help.
Q: What's up with that green plastic leaf thing that comes with my sushi? Am I supposed to do something with it?
A: You mean you don't eat yours?
Just kidding. Those leaves are definitely not edible. They're called baran (sometimes spelled haran), and they're mostly used for decoration. Presentation is really important in Japanese food, even when you're dealing with cheap supermarket sushi. The plastic leaves also serve as dividers in a bento box (a single-portion lunch combo container), keeping your eel nigiri away from your tuna rolls.
The plastic kind have been used in Japan since the 1960s, when supermarket chains started taking off over there. Before that, real leaves were individually cut for the purpose. Baran is the Japanese word for the aspidistra plant, which is what sushi chefs in Kyoto and Osaka used. Over in Tokyo, they preferred bamboo leaves, known as sasanoha.
The real leaves did more than just look pretty, it turns out. Many plants contain chemical called phytoncides, which act as natural antibiotics. Serving sushi with greenery helped preserve the fish and keep it fresh longer. Those zigzag patterns allowed the leaves to release more of the chemical.
Now that we have refrigeration, though, plastic baran are nothing but a reminder of old traditions.
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