Reader Question: Why is it OK to serve beef rare and bloody but not chicken?
Thank you for asking! There are a number of reasons, the first being raw chicken is probably not high on anyone’s must-try list – presumably because one can only imagine it tasting far worse than when cooked. But let me know if you’ve tried it and it’s delicious. And don’t believe all those idiots advocating raw meat / paleo diet etc – cooking food makes it easier to digest, usually tastier and definitely safer. Yes, there are some nutritional losses but also some gains.
Back to the question. There are certain bugs associated with meat and its processing, and some are more dangerous than others. For example Salmonella or E. coli O157. It’s claimed by the industry there isn’t much Salmonella in UK flocks but in a recent survey 8% of the packaging on the 800 million chickens we eat in the UK each year had Salmonella on it. Ick.
So what’s the answer to our first Reader Question:
- There are two really good ways to kill microorganisms: chemicals and heat. Dunking food in bleach before cooking doesn’t do much for the taste so we tend to rely on heat to kill any bugs travelling on food. Different bugs are take different amounts of time to kill at different temperatures, for example at 60°C it takes about a minute to kill 99% of Salmonella – depending on many variables. Higher the temperature, the shorter the time.
- Bugs tend to be on meat and not in meat. Yes there are exceptions some organisms colonise muscle – nematodes like Trichinella spiralis for example – so it is not always true that raw meat is fine if kept away from contamination.
- Red meat such as beef, lamb and duck will get up to adequate temperature to kill bugs but still be pink. As will a turkey leg.
Put all this together and a rare steak is unlikely to have bacteria in it plus flash heating the surface will kill anything you’ve managed to get on it. Yes, there are risks but they are small. Just cut the hooves off and wipe its arse. Lovely. But when cooking a chicken by the time you’ve had it at sufficient temperature / time to kill the bugs the meat will be most likely be pretty much cooked. The risks of getting sick from chicken are still small but they are still there.
For the geeks out there there’s some other biochemistry going on too; at 50°C the myosin coagulates and goes opaque (obvious in chicken or fish) but will also lighten red meat to pink long before the red pigments go. Give it ten degrees more and myoglobin starts going from red to brown. But you can’t always tell done-ness by colour: if you slow-cook red meat it can still appear pink inside because by the time the myosin and cytochrome pigments have reached the temperature at which they unravel, the other proteins have already denatured and done any reacting they’re going to so the pigments stay red as there’s no-on left to play with.
And if you’ve ever wondered why when barbecued the surface of meat sometimes stays pink (to a few mm depth) this is because the nitrogen dioxide (NO2) given off by wood, charcoal etc turns into nitrous acid (HNO2) at the surface that turns into nitric oxide (NO) in the tissues. This reacts with myoglobin to form a stable, pink molecule.
Back to health. A far greater risk is undercooked burgers – when you mince any sort of meat you risk spreading any bugs on the surface throughout the meat. When restaurants prepare steak tartare (mmmmm!) the EHO will have them jumping through all sorts of hoops to ensure it’s consistently safe. There is good reason for this: E. coli O157:H7 has a very low infectious dose (tens of organisms rather than tens of thousands), it will make you ill and can be fatal.
And it’s found in cow shit. And if you want to ingest cow shit it’s far quicker to drink raw milk…