The investment gives another indication of P&G's ambitions to develop its online retail strategy and follows last month's news that is was supporting the launch of , a website that sells its brands directly to consumers.
which is best known for selling Waitrose products online, has also raised a further £13m via a cash injection from Apple Trust - an investment vehicle in which TetraPak billionaire Jon Rausing is the main investor.
The retail business, which was set up almost nine years ago by three former Goldman Sachs bankers and has yet to make a profit, has to date raised £295.5m of equity - more than any other European internet start-up. However, the latest investment values the business at £500m.
According to a report in the Financial Times, P&G said last night that the Ocado deal could prove a "very fertile testing ground" to monitor how people use the internet.
The company, quoted in the paper, said: "We think it is a huge research opportunity. The have a unique business and we can learn from it.
"We have not exactly worked out the research projects we will be looking at, but it will give us a better understanding of how people use the internet."