Bulletproof was appointed by after a three-way pitch in August 2007. Beam and distributor UK are investing £4m in the relaunch.
The new pack features a wraparound swirling illustration by Chris Mitchell, created to communicate the "mixability" message of the drink.
A new blackcurrant variant has also been developed to complement the existing flavours -- apple, cherry, pineapple and tropical.
Publicis Dialog UK created the "add some zing" theme in a cross-agency collaboration with strategists from Bulletproof, Beam and Maxxium. They have revamped all Sourz marketing communications in the UK.
Adrian Turnham, senior designer at Bulletproof, said: "We created a fun and stylish new identity to reflect the lively personality of the brand. The lettering in the brand identity has been specially crafted to suggest the sense of 'zing' present in the fruity-flavoured range."
Gareth Brown, commercial manager at Beam UK, said: "The repositioning of the Sourz brand has been a true cross-agency approach, working with our partners at Maxxium UK, Bulletproof, Publicis Dialog and ZenithOptimedia, and we are delighted with the exciting new marketing platform and the inspiring new packaging which has been developed for the brand."