Image copyright Juicero Image caption Juicero supplies packets of pre-cut ingredients to use in its press

A US start-up that sells a wi-fi connected juicing machine for $399 (£310), has offered refunds after the gadget was mocked on social media.

Juicero makes the bulk of its sales by supplying pouches of pre-cut fruit and vegetables which fit the contraption.

But the product was ridiculed by some after it emerged how the sachets could be squeezed just as easily by hand.

Chief executive Jeff Dunn said the criticism overlooked the "experience" of the machine.

He claimed the "hacking" of the pouches did not produce the same quality of juice. saying the machine was calibrated to deal with different ingredients differently.

But Juicero has now given customers the chance to return the machine and get their money back, including those who bought it at its launch price of $699.

'More than juice'

The San Francisco firm raised around $120m in funding ahead of its launch last March.

It said it was hoping to tackle nutrition and obesity problems, with investors also inspired by the success of businesses like Nespresso which blend a one-time sale of hardware with repeat sales of consumables.

In his blog post Mr Dunn, a former Coca-Cola executive, said that the machine - or 'press' - along with packs of fresh organic produce and a smartphone app combined to "enable a great experience".

The app lets users buy packets of ingredients which cost between $5 and $8 (only people who've bought the machine can order them) - and sends alerts when the produce is going out of date.

And Mr Dunn said that because each pouch of fruit and vegetables was individually tagged, the firm could remotely disable them "..if there is, for example, a spinach recall. In these scenarios, we're able to protect our consumers in real-time".

"The value of Juicero is more than a glass of cold-pressed juice. Much more," wrote Mr Dunn.

"The value is in how easy it is for a frazzled dad to do something good for himself while getting the kids ready for school, without having to prep ingredients and clean a juicer. It's in how the busy professional who needs more greens in her life gets app reminders to press produce packs before they expire, so she doesn't waste the hard-earned money she spent on them."

'Out of touch'

Not everyone was convinced by Mr Dunn's defence of his product.

In response to his blog on Medium, one poster asked: "Are you seriously referring to hand squeezing a bag as 'hacking'."

Another, Tapiwa Muranda, asked: "Malnutrition and obesity are diseases that disproportionately impact the poor and you solve this by selling a $400 (formerly $699) juice press with $5-8 produce packs?"

Meanwhile, Tom Goodwin wrote: "This is everything wrong about Silicon Valley in one note. A sort of unique sense of out of touch that makes people who ship chopped vegetables at 4000% mark up think they are changing the world because of a nice looking app. And then they feel appalled that real people don't see it that way."

But others felt the discussion was unnecessary.

"I know this is going to sound strange to many, but you don't have to buy a Juicero. What are we really getting mad at here?", asked Medium contributor Jeremy Akins.

"There are industries giving people diabetes. The leader of the free world just invited Kid Rock to the White House. I think we can give Jeff Dunn a pass on selling veggie juice to software engineers."