The Red Tractor logo now appears on £6.4bn worth of products - a massive £1.1bn more than at this time last year, the body that runs the assurance scheme has revealed.

Assured Food Standards attributed the rise to the decision by more major brands to use the logo and a rise in the number of own-label lines carrying it.

The logo has recently appeared on Nestlé Shredded Wheat and McCain chips.

Fifty more companies have signed up to the scheme in the past year, with 375 now licensed to use the Red Tractor logo.

"Red Tractor's success is dependent on the support of the whole food chain and we are delighted by the encouragement they give us," said AFS chairman Colin Smith. "We are taking the message to the consumer as part of our long-term strategy to place Red Tractor at the heart of shoppers' decision-making."

AFS said it aimed to increase consumer understanding of what the Red Tractor logo means.

It has launched a media information service and a new consumer website aimed at parents and children, www.myredtractor.co.uk. Red Tractor Week, which ran in July, succeeded in reaching three out of five UK mums, it claimed.

However, research conducted by Defra earlier this year found that just 16% of 3,600 consumers recognised the Red Tractor.

AFS said other surveys had shown far higher awareness levels.