It is a momentous day in meat cookery: the US Department of Agriculture has lowered the recommended minimum cooking temperature of pork by 15 degrees Fahrenheit (9.5C). That may not seem worth a crackling to you, but to pork chefs it is a victory of the light over ancient forces of prejudice and ignorance. David Chang, the two Michelin-starred chef / proprietor of Manhattan's Momofuku restaurants declared in the New York Times this morning the death of a terrible dogma: "Everyone thought the sun revolved around the earth, too."
The revolution is that science has overcome misguided fears about the inherent dirtiness of pigs: the key disease associated with them, trichinosis, appears to have been wiped out in US pork production, mainly because most pigs are raised indoors and chemicals have largely dealt with the parasites. So pork may now be lawfully cooked In the United States at 145F (62C), the same temperature as whole cuts of beef and lamb. That's 20F less than poultry, which must still be cooked to 165F (74C).
The "to" is important, of course - the meat has to reach this temperature internally, and then stay at it for three minutes. Times are crucial. Another US body, the Food and Drug Administration suggests even lower cooking temperatures if combined with longer cooking periods for baked and roasted meats: 130F (54C) for over 112 minutes, or 140F (60 degrees C) for over 12 minutes. (This is not a debate the UK government enters into - but here's the NHS advice on cooking, temperature and hygiene).
Temperatures are a hot topic (ahem) because this is the key area in cooking where issues of safety and enjoyment clash. Chefs, from the highest to the lowest, are very interested in cooking meat at temperatures that would horrify many home cooks. There are savings in energy costs, of course. But more important are the gains in taste and texture.
The science is quite simple. The collagen that makes up most of the connective tissue of meats start to break down and dissolve at around the same temperature that bacteria like E coli die in numbers deemed safe - also known as the pasteurisation temperature. That is around 55C - cooked at that temperature for given amounts of time meat can be relied on to get less tough and more healthy. It still holds oxygen, and its juices do not evaporate much: so more flavour and colour will be retained.
Thus low-temperature cooking is one of the key - though little spoken of - trends of modern professional cooking. It is why sous-vide (slow cooking in vacuum packs, in a water bath at a set temperature) is said by Heston Blumenthal and many others to be the most important cooking innovation of the last century. Forget "browning" as a way to seal in flavour: slow'n'low is the key, say Heston and co.
Of course, a combination of inadequate cooking and poor food hygiene is the fastest way to put diners in hospital. But the prizes low-temperature cooking offers are enticing. Amazing flavour and texture effects can be got from meat, vegetables and fish.
Sous-vide is also brilliantly idiot-proof. "All you have to do is prep it, bag it, note the time and temperature, and snip open the bag to plate," Antony Worrall Thompson, another slow-low convert, says. "The machine is another pair of hands in the kitchen." Beef steak, one of sous-vide's most spectacular advertisements, is bathed in restaurant kitchens at 56C for as much as 12 hours - then quickly seared in a pan to finish it.
But how many of us would contemplate chancing a Sunday roast cooked at the temperature of hot bathwater? I've borrowed a sous-vide machine and done sirloin steaks at 56 degrees in it with great success. This was beautifully produced beef, from Millers of Granttown. That makes sense, at these temperatures. "You don't want to be fooling around at 60C with a £2.99 battery chicken," growls Worrall Thompson.
Low temperature cooking in the oven is rather more challenging. Crucial are a good oven that circulates heat properly and a digital probe thermometer. Cooking at around 55-60 degrees, you must know that the core of the meat has got to those temperatures. Otherwise, a world of pain and shame may lie ahead.
But it's worth the risk. I've been cooking lumps of beef fillet at my (not great) oven's lowest setting for an hour, searing it quickly first and then wrapping it in non-PVC cling film - the temperature is too low for that to melt. (Here's a recipe from TV's James Martin, though I would question the cooking times he gives.) It was spectacular. The meat was amazingly tender: it had the strength under the teeth of medium-boiled cauliflower, and other than those sous-vided sirloin steaks I've never eaten something with so much taste. It was verging on scary.
What do you think about low temperature cooking - is pink pork for you? Would you take the risk of cooking pig at bathwater temperatures?
