If it doesn't look red, they simply abuse the waiter

Hopefully the Surrey trading standards' investigation will deter those owners and cooks who are breaking the law by using potentially dangerous levels of colouring in popular Indian dishes, chicken tikka masala in particular. None of us wants to spend good money on food which we know triggers hyperactivity, asthma and deadly diseases long term. We do not eat like this in our homes and are careful to go to eating houses where we know there is no extra paint thrown in. South Asians I talked to yesterday, including diligent and reliable folk in the vast Indian restaurant trade, are furious. One spoke for the rest when he said: "These bloody idiots are giving the whole industry a bad name and our business will suffer."

Hopefully the Surrey trading standards' investigation will deter those owners and cooks who are breaking the law by using potentially dangerous levels of colouring in popular Indian dishes, chicken tikka masala in particular. None of us wants to spend good money on food which we know triggers hyperactivity, asthma and deadly diseases long term. We do not eat like this in our homes and are careful to go to eating houses where we know there is no extra paint thrown in. South Asians I talked to yesterday, including diligent and reliable folk in the vast Indian restaurant trade, are furious. One spoke for the rest when he said: "These bloody idiots are giving the whole industry a bad name and our business will suffer."

And that is the pressing worry. Individual immigrants of colour cannot behave badly without dragging all the rest of us down. I have always warned my children that, if they do wrong, they will harm themselves and countless other brown skinned people. It is an intolerable pressure. We are constantly called upon by this nation to prove that we are not exceptionally wicked, devious, untrustworthy, criminal, dishonest, uncivilised. Even now, when chicken tikka masala has become Britain's favourite food, South Asians are told they smell, that their cooking offends neighbours, that their food is never as worthy as that of the French or Italians. Chinese, Thai and Vietnamese Britons understand this well. They too have suffered generic slander when too much monosodium glutamate was found in food served by some restaurateurs. And when the BSE crisis was blamed on Chinese food, the population was traumatised. (And I haven't even mentioned the dog meat in stir fries and rat biriyani.)

If 50 tapas bars had been found serving food with dangerous levels of additives, all Spaniards and their food would never be condemned in the same way. There is a long history of enmity between Spain and Britain but no embedded history of inequality which goes back to the Empire. I have an old, white settlers' recipe book published in Kenya, and it is a document of paranoia. There are warnings about the strange foods, about spicy dishes and essential Swahili expressions: mostly accusations of theft or complaints about unclean hands and other expected "bad habits" of black servants.

There is another issue too. In a driven market economy, it is the business of business to supply what the punters want. Addicts of bright red chicken tikka masala think they are being diddled if the dish arrives pale and subtle. They shout, accuse waiters of ripping them off (again, the same stereotypes of Asians as blackguards), demand the real thing. I have witnessed this at a restaurant in Hammersmith, an honest curry house trying hard to use natural ingredients. Tanked up with lager, men demanded their raging red dish and got abusive when the waiter explained that they used tomato purée, which made the sauce look dull red. Millions may be addicted to Asian food, but it is their version and this is what suppliers feel they must deliver. As I have argued, authenticity is a reactionary concept. It is great that chicken tikka masala is a British invention, and it can be cooked to perfection without using additives.

But for a large section of the eating public, the dish has to be artificial for them to enjoy it. That is the nature of addiction. Within minutes of tasting oven-ready potato wedges or frozen hamburgers, children can start to reject real potatoes and home-made patties. Bad food is a way of life in this country for millions and, until consumers learn better, producers will carry on giving them rubbish, even if it damages health. The market, they say, has no morality. How else do the makers of cigarettes and booze live with what they do?

It is good that this survey has shown up bad practice. Fear and pressures from conscientious suppliers of Indian food will force change for the better. But it is important to be aware that colour matters in more ways than we think.