The feline-friendly competition is being launched to mark the brand's tie-in with the forthcoming children's film Garfield 2.
However, rather than forcing parents to take on the wild cat as a pet, the winners will sponsor a tiger and visit it in India as part of a ten-day family safari.
Other prizes include 50 giant and 1,200 small Garfield toy cats, plus 500 DVDs of Garfield 2.
Running to coincide with the film's cinema release, the on-pack promotion is being supported by a £3m campaign that will include online and outdoor activity.
Consumers have to answer a question that will appear on special 500ml and one-litre bottles and 200ml multipacks. Ninety nine families will then be invited to a prize draw at London Zoo in October, when the two winners will be picked.