Innocent sells two million bottles of its smoothies every week
Coca-Cola has bought a £30m stake in Innocent, the British fruit drink and "smoothie" maker renowned for its ethical ethos.
Innocent says the minority investment will allow further European expansion.
The firm was set up in 1999 by three friends who spent £500 on fruit, turned it into smoothies and sold them at a small London music festival.
Its founders insist its "socially and environmentally-aware" stance will not be compromised.
They will continue to lead and run the company, based in Shepherd's Bush, west London, and its production practices will be unchanged, the firm said.
None of the invested cash will be paid out to shareholders.
In a statement, Innocent said it chose Coca-Cola as an investor because "as well as providing the funds, they can help us get our products out to more people in more places".
Co-founder Richard Reid said: "Every promise that Innocent has made - about making only natural healthy products, pioneering the use of better, socially and environmentally-aware ingredients, packaging and production techniques, donating money to charity and having a point of view on the world - will remain.
"We'll just get to do them even more."
Innocent employs 275 people, has a turnover of more than £100m and sells about two million smoothies per week.
It already supplies retailers as far afield as the Netherlands, Denmark, Germany and Austria.
James Quincey, group business unit president for Coca-Cola Europe, said the group was delighted to be investing in Innocent.
"We have long admired their brand, their products and their unique approach to business," he added.
Innocent prides itself on its ethical values, aiming to make "only natural healthy products".
Meanwhile, Coca-Cola was recently told to correct an advertising campaign in Australia because its claims that Coke did not make you fat or rot your teeth were deemed "misleading".
However, it is not the first time a smaller company has been acquired by an unexpected buyer.
In 2005, organic chocolate maker Green & Black's was bought by Cadbury Schweppes.
Green & Black's introduced the first Fairtrade product in the UK when it launched its Maya Gold chocolate in 1994.
At the time, Cadbury's had opposed the principle of fixing the prices it pays to cocoa farmers, though it has since committed to Fairtrade agreements of its own.
And in 2000, sceptics asked if Ben & Jerry's, the ice cream maker renowned for its social and environmental values, was selling out after being bought by the global giant Unilever.
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