Last week unconfirmed rumours emerged in the press linking Coca-Cola to the leading smoothie manufacturer, but Hero and Heinz are also rumoured to have held investment talks.
Innocent is looking to secure a £30m investment for a minority equity stake in the business to fund its European expansion plans.
"We're looking for someone who can contribute financial clout and help with the mission," said co-founder Richard Reed.
Innocent is thought to be seeking a trade investor rather than private equity, in order to secure a higher valuation and bring on board corporate "smarts".
Though Innocent had a tough 2008, with sales falling 22% while fruit costs soared, it fended off a challenge for market dominance from PepsiCo's Tropicana, which was launched early in the year.
Innocent's market share fell from 76% to 59% the week of Tropicana's launch, but has since grown to around 78% [IRI]. However, the value of the overall smoothies category has fallen 25% over the year.
Despite a turbulent year, city brokers are confident Innocent will secure a valuation based on a multiple of two to three times its sales, which would value the business at approximately £200m to £300m.