Pingmag's got a lovely feature on Japanese packaging design that imitates natural materials, such as fake printed cardboard bamboo sheaths, plastic fake "bamboo" bottles, and other natural/plastic hybrid packaging techniques.
Bamboo is naturally divided into sections and here it ingeniously functions as the mould and the container for the jelly as well. Efficient! Amazing! Perfect! But to temper the delight: There is an extra tool required to make the yokan slip out of its container. This involves additional effort.
In contrast, the plastic replica is easier to open.
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