Australian studio Heliograf teamed up with Vert Design to produce Holy Carp! – a plastic-free, compostable alternative to the fish-shaped soy sauce packaging

The Holy Carp! packaging is made of bagasse pulp, a fibrous by-product of sugar production, and was designed to be used by the same restaurants that may have once offered the plastic packets with their takeaway sushi.

Just like with the plastic packaging, Holy Carp! can be used as a dropper, allowing diners to squeeze the fish's "belly" to squirt small amounts of soy sauce on their food.

The project follows on from Heliograf's Light Soy lamp, a giant version of the iconic soy sauce fish that was intended as both a loving homage and an awareness-raising exercise about its problems.

The single-use plastic packaging is too small for recycling and so often ends up in landfill or, worse, in the oceans, where it can be mistaken for food by birds and marine life.

Having had the idea to adapt paper-pulp sauce containers for this purpose, Heliograf approached Vert Design, its collaborator on Light Soy and creator of the lamp's plant-pulp packaging.

The bagasse-pulp fish has a diaphragmatic shape that allows it to function as a dropper when squeezed, with a slight doming of the belly area, just like in the plastic equivalent.

The tail fin becomes a grip to help with easy opening, while a flanged edge creates a leak-proof seal, and the tiny dropper hole below the fish's eye can be optionally closed with a compostable sticker to prevent spills.

Unlike with the plastic fish, which are pre-filled in factories, the Holy Carp! fish are designed to be filled fresh at the restaurant and used soon after, with Heliograf and Vert Design advising that the packaging retains its integrity for 48 hours.

With a 12-millimetre capacity, Holy Carp! is larger than the plastic fish, both for ease of use and manufacturing, and to account for the fact that customers often grabbed the old packets by the handful.

The packaging formula involves mixing bagasse fibres with a food-safe wax that eliminates the need for any lining, which would often be made of plastic or PFAS, and the product is expected to break down in four to six weeks in normal home composting conditions.

For more information on the design, visit Heliograf's website or follow them on Instagram .

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