Who invented? Coffee?

Regrets: John Sylvan (pictured) says that he often wishes he had never invented the Keurig coffee pods

Keurig is currently thought to be one of the most popular at-home brewing systems in America. Last year the company sold 9.8 billion Keurig-brewed portion packs and earned $4.7billion.

The design is simple - a small plastic capsule containing ground beans that can be put into a machine to produce a cup of coffee at the touch of a button.

However despite the multi-billion pound success of the company nothing has been done to try and make the packaging of the popular Keurig pods recyclable.

And Mr Sylvan insists this will never happen.

'No matter what they say about recycling, those things will never be recyclable, ' he said.

'The plastic is a specialized plastic made of four different layers.'

Mr Sylvan, who co-founded the company with Peter Dragone, added that the unique plastic used in the K-Cups - known as plastic #7 - is only recyclable in a small number of cities in Canada, and cannot as yet be processed yet in the United States.

Unfortunately the plastic is also integral to the unique design of the pods. It ensures that the coffee inside stays completely protected from any outside elements and remains completely intact while the coffee is being brewed.

The popularity of the simplistic coffee pods has also come across the shores to the UK. Adverts for K-Cup featuring the slogan 'Brew the Love', enticed American audiences. And in England thousands of customers have been lured into buying Nespresso machines following similar adverts featuring George Clooney.

Nespresso is now the most prominent capsule company in the UK. The machines do not take the Keurig capsules but take similar plastic ones and Nespresso has established its own sustainability advisory board.

Mr Sylvan also confessed that despite his earlier dedication to the brand, he no longer drinks coffee made using the capsules.

In 1995 he had to go to hospital with heart palpitations after testing up to 40 cups of his coffee a day. He now no longer even owns a K-Cup machine and only drinks filter coffee.

George Clooney has helped popularise the Nespresso brand in the UK, a similar version of the K-Cups

Damaging: Keurig has come under fire on numerous occasions from environmentalists who claim that the number of K-Cups sold in 2014 alone would circle the earth 12 times if they were laid down end-to-end

Keurig has come under fire on numerous occasions from environmentalists who claim that the number of K-Cups sold in 2014 alone, and subsequently put into landfills, would circle the earth a staggering 12 times if they were laid down end-to-end.

They have started a Kill The K-Cup campaign, which features a YouTube video showing the world being destroyed by the plastic coffee capsules.

But despite the continued criticism, Keurig Green Mountain, the brewing system's parent company, has yet to come up with a viable solution to the problem, despite insisting that they have been trying to find an environmentally-friendly alternative since 2006.

'It's a warranted criticism, ' Monique Oxender, chief sustainability officer for Keurig Green Mountain, told The Salt earlier this year. 'We're not proud of where we are right now, and we're committed to fixing it.'

Alternative option: Mr Sylvan insists that he has managed to create a new design for the K-Cups which would be far more environmentally-friendly than the ones currently being used

Not according to Mr Sylvan.

The entrepreneur insists that he has come up with an alternative design to his original creation which would involve relying on the same kinds of materials used for foil ketchup packets.

But while Mr Sylvan is convinced that he holds the answer to Keurig's ongoing environmental concerns, he added that the company have thus far refused to trial his new design.

'I told them how to improve it, but they don't want to listen, ' he added to The Atlantic.

'There's a much better way of doing it.'

Ironically, Mr Sylvan's current work, running energy efficient solar energy company ZonBak, requires him to be much more mindful of the environment, which is perhaps why he is suffering from such feelings of guilt over his most infamous creation.