Extreme Cuisine: I watch UKTV Food so you don't have to. The chefs have bad habits.
Starting with the least offensive and moving onto the worst
But, why wait?
"In the restaurant, I always use wild," says Jamie. "At home, a bit of farmed is alright." And so Jamie dribbles olive oil over his farmed salmon, places it in a tray full of vegetables and puts the whole concoction in the oven at 180 degrees.
Salmon is one of the richer sources of Omega 3 and 6 oils - one reason for the upsurge in demand for it.
At 180 degrees, the oven is very hot. Omegas are very volatile. According to lipid chemist Mary Enig, they start to go off at around 70 degrees.
Farmed salmon starts with less Omega oils than wild salmon. The reason is that Omegas develop from the fish's natural feeding environment - particularly seaweed.
At 180 degrees, the oils burn off and change their nature. Oil refining is a heat-driven process and, by cooking fish at extreme heat, arguably, you strip them of their natural goodness.
And why did you buy them? For their natural goodness.
Leaving aside the desirability of eating farmed salmon - a dubious endorsement by Jamie - note how, the world over, various fish-dependent cultures have resisted cooking salmon or developing a cooked salmon cuisine.
To a certain extent, culinary attitudes have been shaped by the fish's migratory nature. The catch-them-while-you-can element forced humans to find a way of preserving. Smoking, curing and marinating are all, in part, responses to that necessity.
But of the three big salmon regions - Ireland, Scotland and Scandinavia - none has a developed salmon cuisine. Even the French are reluctant to do more than warm the king of fish gently. Saumon en papillote, a French favourite, is cooked with the salmon in a paper parcel. The paper takes the heat and protects the salmon which, in effect, is left to lounge in its own private sauna.
From a health point of view, salmon should, at best, be lightly poached in a mixture of milk and water to keep the temperature low.
The master of fish cuisine, Georges Lassalle, who wrote The Adventurous Fish Cook, says grilling fish is a legitimate activity only if the fish is scaly and the grill addresses the skin. Grilling flesh-up is destructive.
Cooking in oils at high temperatures is one of the more puzzling habits of celeb chefs and it began when Ken Hom began popularising Chinese food and wok cooking.
We are all wok cooking nowadays even when we use our frying pans. Watch the celeb chefs and you see how nearly all begin a dish waiting for the oil in the pan to smoke.
There are exceptions to this insanity. Rick Stein customarily starts off with a nut of butter and sautés gently, although he too has his off days and has been known to reach for the olive oil.
To sauteé or to fry?
Researchers at the World Health Organisation are trying to clarify the health impact of hot frying, after Scandinavian researchers identified a known carcinogen, acrylamide, in fried starchy foods, demonstrating that we treat cooking methods lightly at our peril.
Paul Pitchford, who writes about the health benefits of wholefoods and is a student of Chinese medicine, tells us that the Chinese would normally add cold water to the wok, again to keep the temperature down.
Tamasin Day-Lewis is an opponent of the fast food culture of celebrity chefs, the type who cook hot and fast, but Tamasin tops her stuffed tomatoes with extra virgin olive oil and then cooks at 220 degrees in the oven. Although olive oil is less volatile than the essential fatty acids, taking it up to 220 degrees seems perilous to me.
Enough about oil.
Among their other bad habits, thoughtlessly seasoning every item of cooked food being one, celebrity chefs have a marked tendency to ignore kitchen hygiene rules.
The blasé way they breeze around the kitchen collecting and handling ingredients sends a message that food is safe. Handled and cooked properly, it is.
But when Nigella handles meat, she appears to reach over and grab a handful of herbs from a bunch on the kitchen counter. She and many other chefs give the appearance of using the same cutting board for meats and other dishes, including salads. Both practices carry the risk of cross-contamination, surface bacteria from the meat being transferred to other foods that are not then cooked.
Few celebs seem to wash their hands. This might be construed as very pedantic. The requirements of television programme-making dictate that we should not lose valuable air time watching Nigella rinse her hands between cutting meat and reaching for basil, or that time spent watching Gary Rhodes scrub between recipes would mean less time listening to him praise a good seasonal lamb chop.
Hmmm. All very well but poor hygiene, like the cooking methods that damage food, can make the difference between eating well and being ill.
By the way, that Delia. She even recommends you don't wash the supermarket's pre-washed lettuce leaves. Highly convenient, but before taking her advice, ask first if the lettuce was chemically scrubbed. Or ask your kids, how do they like their chlorine.