Why you'll never see colored seaweed

Imagine the creative things you could do with food if "nori" seaweed came in different colors. The bento boxes that could be made, if we had pink, blue, yellow or other seaweed. Many other foods are colored to enhance their appeal and / or usefulness. But it will never happen with seaweed, because it is prohibited by law. 

The reason is that it would be difficult to tell whether the quality of the seaweed is good or bad if it was colored. The law stipulates that the original color of the seaweed cannot be disguised with colorants and poor quality seaweed should not be enhanced to make it look good. For the same reason, the use of colorants in meat, fresh seafood, vegetables, tea, tofu, miso, soy sauce, etc. is also prohibited or restricted.

There is no colorful seaweed, but instead there is "printed seaweed" with pictures and letters printed on the seaweed. You can also buy punchers for creating your own designs on seaweed. The 100 yen shop of a great collection of punchers specifically for food. You can get punchers that will create shapes, animal designs, seasonal themes and even characters on your sheets of seaweed. So while you may not be able to use different colors of seaweed to make bento fun, you can use printed seaweed instead.