Jakarta (Reuters) - Jakarta food and beverages retailer Ong Tek Tjan sells ice cream in cups his customers can eat afterwards, instead of throwing away - they are made from seaweed and taste like jelly, in flavors from peppermint to green tea.

Indonesian startup Evoware, which makes the cups, as well as other containers, from farmed seaweed free of chemicals, is relying on its biodegradable alternative to plastic packaging to reduce contamination of the environment.

“I too support this environment-friendly cause,” said vendor Ong, who uses Evoware’s Ello Jello container to serve ice cream, though he feels consumers may take time to adapt to the product that is pricier than current options.

Indonesia, which has some of the world’s filthiest rivers and once-pristine beaches littered with plastic waste, has joined a United Nations-led cleanup drive after being rated the second-biggest plastic marine polluter, behind China.

Evoware co-founder David Christian said the idea of seaweed-based edible packaging was spurred by his desire to fight an explosion in plastic waste over the last few years in his home city of Jakarta, Indonesia’s capital of 10 million people.

“I saw how much plastic waste is produced here, which takes hundreds or thousands of years to degrade and contaminates everything,” Christian added.

From the first product it developed, the seaweed-based jelly cup, Evoware is expanding into other types of packaging, such as dissolvable sachets for coffee or seasonings.

Indonesia produces 10 million tonnes of seaweed each year and targets 19 million tonnes by 2020, said Christian.

But Evoware’s products, now made by hand, still have some way to go before they can compete with plastic on price.

The edible seaweed Ello Jello cone can be up to five times more expensive than ordinary crepe cones, Ong says. And it uses wrappings of plastic and paper to preserve its texture.

“I hope in future the packaging could be better and not use plastic,” said one customer, Vince Lantang Helda.