Green and even brown-coloured smoothies could soon be making their debuts under the Innocent brand after more than six years of development work, The Grocer has learnt.

A number of kiwi recipes, including one that does not contain bananas - present in all its smoothies at the moment - are currently being finalised and could be on shelves later this year.

Innocent said it had developed a gentler pasteurisation process that maintained the taste, flavour and colour of the kiwis, which will be blended with other green fruit such as apples and limes.

Until now, the company, which has spent the past six years testing recipes with kiwis, found the heat treatment involved in the pasteurisation process turned the smoothies a "sludgy brown" colour.

When it tried using spirulina seaweed to achieve a green colour, the product separated and had an odd taste, said product development manager Lucy Thomas.

Innocent offers the biggest range of smoothies in the UK with more than 15 lines, but until now a green drink has eluded it.

There are kiwi-based smoothies available, including a Kiwi & Mango Fusion product from smoothie company Puro, but they are typically made without pasteurisation, a key element of Innocent's production process.

Despite its less appealing colour, a brown smoothie could also be in the offing following positive feedback to a prune & fig recipe, said Thomas. "People are warming to the idea of brown but it's a difficult colour to communicate," she said.

Less controversial is the launch of a first smoothie for kids containing the superfruit pomegranate. The pomegranates, blueberries & blackcurrants Smoothie for Kids will be available from next month.