Tesco is launching what it claims is the first double concentrate squash in an environmental move it hopes will also tap into new growth in the cordials category.

Fruit squashes slumped by almost 4% last year, according to TNS, following several years of people switching to trendier options such as smoothies. However, the market has grown 4.7% since January - a trend Tesco believes is linked to people leaving bottled water and going back to the tap.

An 8% fall in bottled water sales in the past year is a direct result of more people opting to drink tap water, said Tesco soft drinks buyer Jane Potter.

"Generations of families grew up with squash as it was a cheap way of quenching one's thirst and it stayed a household fixture until the mass arrival of fruit juice in the 90s," said Potter. "But since the beginning of the year we have seen an increase in green-minded shoppers returning to squash. The double concentrated concept is an exciting one that has already worked well for us with detergent."

Following a trial in a handful of stores last month, Tesco is replacing its 14-strong own-label squash range with the double concentrate product, rolling out now to 1,500 stores.

Prices of the 750ml, 1.5-litre and 3-litre bottles have been increased to account for the double concentrate, with the new three-litre bottle costing £2.89, compared with £1.49 for the old half-strength version.

Total annual packaging volumes have been cut, with 1,400 tonnes less PET used in the new range, a fact flagged up on the bottle labels.

Other environmental initiatives include 100%-recycled plastic for the 750ml variant and recycled shelf-ready packaging.

Premium drink brand Bottle Green said it had also experienced a marked upturn in sales so far this year, with an increase of 17% across its cordials range compared with 2007. Marketing director Andrew Mallinson said the company had consequently increased its listings with Tesco from five to all seven variants.