I won't be buying too many spit-roasted chickens from my local supermarket this Bank Holiday weekend, and I don't much fancy houmous either, following this week's BBC Whistleblower documentary. The flouting of procedures, falsifying of records and levels of hygiene exposed variously in Tesco, Sainsbury's, Katsouris and Crown Chicken were shocking. But the trouble with these exposés is it's easy to gain the impression the problem is systemic: if this is happening at a Tesco in Woodford Green and a Sainsbury's in Didcot, it's happening across the country. Asda, Morrisons, Waitrose, too, are guilty by default. A nervousness about the food standards of the supermarkets seeps into the subconscious. Yet the documentary also showed, quite clearly, that the right procedures are in place. And a more sober reflection from watching the documentary is that this is one of the perils of controlling humans: as every manager knows, you can't stop some people from cutting corners, wilfully disobeying or ignoring rules, and acting in sometimes spiteful and slovenly ways. Speaking to the supermarkets in question this week, it was clear that while expressing concern with specific malpractices - and you can be sure heads have rolled and more will follow - they also felt stitched up again by the implication of a systemic failure, as well as a number of inaccuracies in the BBC's reporting (see p6). The fact is that, as a rule, the UK's supermarkets are the safest in the world, with safeguards at times that are positively gold-plated. And thank goodness, also, that Brussels climbed down, two weeks ago, from its exemption of small food businesses from HACCP rules. Basing the safety of a food-serving site on the number of people that work there is ludicrous. Big or small, it's procedure but above all implementation that counts.