He added: "Shoppers want to know more about where food comes from. If you are just a noun, like 'onions', you are in the commodity business, unless you can ad an adjective - local, sweet, fiery, peeled, chopped. I wouldn't be surprised if sales of processed onions go up while fresh goes down, as we have seen with potatoes."
Suggesting an industry-wide campaign to emphasise onions' role in healthy eating, he said: "I have seen from working in the fresh berry business that with a couple of hundred thousand pounds of PR you can really shift the public's attitudes."
Professor Harm Veling of Radboud University in Nijmegen, the Netherlands, said on this point that consumers' dietary intentions are often unrelated to their actual food choices. "People need to be reminded of their goals at the right moment. Making the healthy choice the impulsive choice requires a combination of interventions and product innovations."