|Dispelling five common consumer food safety myths|
|Thursday, 16 February 2012|
We all know that you have to cook pork until it's grey, that you can't leave anything with mayonnaise out for too long, and that a quick whiff tells you if food's gone bad. Except that each of those 'facts' is wrong. Food safety experts to pull together a list of consumers' most common food safety myths.
Mayonnaise is a death trap
Actually, mayonnaise is an ingredient "with penicillin-like properties," says Don Zink, senior science adviser for the US FDA's Center for Food Safety and Applied Nutrition. Mayo is a homogenised mixture of oil and water, with egg white to stabilise it. The salt and vinegar or lemon juice makes the tiny droplets of water suspended in the mixture deadly to microbes.
So for a safer salad, don't hold the mayo. Putting in more mayonnaise only makes it safer, he says. No, not forever, but certainly long enough for a picnic.
Pink pork is a no-no
Not any more. Last year, the US Department of Agriculture revised its decades-old guidelines and now says that pork, and all whole meat cuts, have to get to only 63ºC internally, not the 71°C the agency had previously suggested. That means a pork roast can have a rosy interior, not the dead grey of your mom's roast. The change comes because despite everything you were ever told, there's no trichinosis in commercial pigs. The parasitic disease is caused by eating raw or undercooked meat infected with roundworm larvae. It was a problem years ago, but no longer exists in commercially grown pork.
You can smell when food's gone bad
Microorganisms divide into two main groups, those that cause spoilage and those that cause disease. There's some overlap, but many bacteria that cause disease don't cause overt spoilage.
"You could have loads of E. coli or salmonella or listeria in a food and it would not appear to be spoiled or have any off-odor or flavour," says the FDA's Don Zink. The only real way to judge the safety of a food is by what you know about how it was prepared and stored.
You should wash produce and meat
This one seems like a no-brainer: Washing makes things cleaner, right? Wrong. People think they can make produce safer by rinsing it under the tap, but that's a holdover from the days when they carried in vegetables straight from the garden, still dripping with dew, dirt and the occasional slug.
Bagged leafy greens don't need to be washed at all.
"Just open the bag and put them in the salad bowl," says the FDA's Zink. They were already washed in a sanitising solution at the packing plant that, frankly, was probably a lot cleaner than your kitchen.
Micro-organisms actually bond to the surface of the food item. "You are not going to rinse them off, it simply won't happen, they cannot be washed off," he says.
All washing might do is "remove the snot that some three-year-old blew onto the food at the grocery store," says the ever-forthright Powell at Kansas State. Washing "lowers the pathogen count a little, but not to safe levels if it's contaminated."
Even though half the recipes involving meat tell you to rinse it off (especially chicken and turkey), this is unnecessary and actually dangerous, says Elisabeth Hagen, under- secretary for food safety at the USDA.
"Rinsing meat or poultry with water can actually increase your chance of food poisoning by splashing raw juices and any bacteria they might contain onto your sink and counters."
If the water touched your hands, they're clean
Think a quick rinse of your hands before you handle food is good enough? Nice try. A good hand-washing takes at least 20 seconds, says Doug Powell, a professor of food safety at Kansas State University, who has written research papers on the topic.
The real cleansing is done by the friction and force of rubbing your hands together, along with the soap. The temperature of the water doesn't really matter, as it takes 71ºC to kill bacteria, which would be fine except water that hot would also give you third-degree burns. But warm water does make it more likely you'll spend the necessary 10 seconds scrubbing under vigorously flowing water. And then another 10 seconds of vigorous rubbing with a towel.
"The friction rips the microbes off your skin," Powell says.