An odd thought crossed Katsuhiko Sakakibara's mind upon spying a mound of garbage made up of plastic plates, cups and containers at a local gourmet event: What if you could eat them?

Sakakibara, 42, has now turned his flash of inspiration into a business that makes edible tableware and cutlery to sell to environmentally conscious consumers.

He is not alone, though. Numerous Japanese companies are now offering edible plates, trays, chopsticks, straws, coffee cups and other utensils in response to growing public concern about marine pollution caused by plastic waste, and sales channels are expanding.

Sakakibara's company, Marushige Seika, based in Hekinan, Aichi Prefecture, sells dishware products called "E-Tray" for "yakisoba" noodles, "takoyaki" ball-shaped snacks and other meals for take-out or other uses. 

The brand name is a combination of "eat" and "tray," with the "E" also standing for "edible."

The company, originally a producer and wholesaler of soft-serve ice cream cones and "monaka," a macaron-like traditional sweet made of bean paste sandwiched between thin wafers, now finds itself focused on how to make "garbage" taste good.

"We struggled to achieve a good balance between the tenderness as a food item and the stiffness as a plate," said Sakakibara, Marushige Seika's senior managing director. "Then we added potato starch: problem solved. The plates can also serve curry and other soup-based dishes."

If people don't want to eat E-Tray's dishware, it still ends up being better for the environment than biodegradable plastic as it decomposes at a much faster rate. The company's edible items only take several days or a month at most to do so in soil, Sakakibara said.

Sales of the company's edible plates have jumped three-fold in the past two years as pollution from plastic waste has increasingly become a social issue. Marushige Seika first marketed the plates eight years ago.

It also sells edible chopsticks made from "igusa" rush used for food, and is soon set to release a spoon made from wheat. The company is also developing an edible drinking cup.

Kimura Alumi Foil Co., based in Osaka's Chuo Ward, offers edible containers from its "Tabereru Utsuwa" brand.

The cup-shaped wrappers made from foodstuffs rolled into a sheet are designed to serve side dishes or condiments.

Customers can consume ones made from nori seaweed, "oboro konbu" (dried shredded kelp) and "katsuobushi" (boiled, dried, smoked and fermented skipjack tuna). Some are made from daikon radish, carrots and soybeans, giving assorted colors from the vegetables' various pigments.

The edible containers have also become a hit at sushi parlors outside Japan, according to the company. 

Kimura Alumi Foil produces aluminum and resin cup-shaped containers widely used for "bento" lunch boxes sold at convenience stores.

To help reduce plastic waste, the company initially developed a biodegradable container, but the company eventually found more potential in the edible products as they decompose quicker.

"We haven't been able to use them for convenience store bento because they absorb moisture over time," said the company's president, Yuichi Kimura, 68, adding that Kimura Alumi Foil is "developing a new product to resolve the matter." 

Edible straws made from a seaweed-based material are now available in the United States. Leak-proof coffee cups made from biscuits developed in New Zealand are becoming popular and are being used by the country's airline on some routes.

JAPAN'S THERMAL RECYCLING QUESTIONED

Plastic household waste is generally classified into two categories: plastic containers and packaging and plastic products.

The former includes PET bottles, single-use shopping bags, food trays and other containers and Styrofoam products, making up about 70 percent of all plastic waste.

Japan generated about 9 million tons of plastic waste in 2017, including both household garbage and industrial waste. Of that figure, 7.8 million tons were recycled, according to the Plastic Waste Management Institute.

But only a small portion was recycled as plastic. About 70 percent of the waste was used for thermal recycling to utilize the heat released by the combustion for power generation and other purposes. Thermal recycling is not regarded as legitimate recycling in some countries.

Last year, leaders of the Group of 20 nations adopted the "Osaka Blue Ocean Vision" at their summit in Osaka Prefecture to reduce additional marine plastic litter to zero by 2050.

Microplastics, which are generated when plastic products are degraded by ultraviolet rays, ocean waves and other elements into fragments of 5 millimeters or less in length, have sparked significant concern worldwide over damage to the marine ecosystem.

Microplastics in oceans originate from plastic plates, cups and other garbage from take-out meals that people have discarded.