Heinz will sell the first 3,000 bottles of its latest Tomato Ketchup exclusively through Facebook UK - the first time the social network site has been used to flog groceries, it claims.

From Monday, consumers will be able to buy Heinz Tomato Ketchup with Balsamic Vinegar through the Heinz Tomato Ketchup UK page on Facebook. The rest of the 1,000,057 bottles will be on shelves from 23 March.

The commercial potential of Facebook is increasingly understood by marketers and has already been harnessed in the fashion world, with online retailer Asos allowing consumers to buy direct from the social network site when it opened a Facebook store in January.

But this is a first for food and the move would bring Heinz "closer" to its 40,600 Facebook fans as part of the company's significant investment in digital strategy over the past six months, claimed Heinz marketing manager Ian McCarthy.

Heinz only created a Facebook page for its Tomato Ketchup last October, but was now in "constant dialogue" with Facebook and advertised with it every day, he added. From Monday, Heinz advertisements on Facebook will drive traffic direct to the limited-edition sauce tab.

Heinz lovers will be able to buy a bottle (rsp: £1.49) using a payment system embedded into Facebook. Facebook does not take a cut, making money instead through payments for advertising and credits.

Online grocer Ocado said it was watching "with interest", but pointed out people could buy multiple foods in one transaction on its website, whereas Heinz was only selling one product. "We'll be very keen to see how it goes," a spokesman added. "The online retail space is growing very quickly and there's room for everyone."

But Richard Buchanan, director of consulting at brand and marketing consultancy The Clearing, questioned how significant a move this was. "Does this mean more food companies are going to start selling direct through Facebook? No; that's the job of online grocery," he said. "Will consumers think I'm going to the Jaffa Cakes page to buy Jaffa Cakes and the Weetabix site for cereal? No."

It was, however, a really cost-efficient way of generating buzz around NPD and reaching a wide audience, he added, because each of the 3,000 people who buys a bottle on Facebook will have an average of 130 friends.

Heinz had struck on an innovative way of engaging fans and creating a buzz around NPD, agreed Guy Grimsley, consultant at The Value Engineers, but warned only the most well-loved and "iconic" fmcg brands could get a big enough Facebook fanbase to make it effective.

The balsamic vinegar ketchup is the first limited edition Heinz Tomato Ketchup. Heinz has 77.3% of the £164m ketchup market.

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