Are cut onions magnets for bacteria???

Joined Dec 23, 2000
I receive a newsletter with interesting odds and ends, and the most recent one has a piece on onions that quotes a food chemist at Mullins Food Products (never heard of it) that says

"...onions are a huge magnet for bacteria, especially uncooked onions.You should never plan to keep a portion of a sliced's not even safe if you put it in a ziplock bag your refrigerator. It's already contaminated enough just by being cut open and out for a bit, that it can be a danger to you."

You can imagine what he says about the diced onion sitting out at at the hot dog stand.

What the HECK is this? If it's even remotely true, I've been cheating  death for over fifty years. /img/vbsmilies/smilies/eek.gif

Worse, I will shortly be chopping twenty-five or so pounds of onions to set out for unsuspecting patrons of our Rotary hot dog stand  over the Father's Day weekend.

Stop me before I kill again!


On the other hand, it's exactly what I've done for the last fifteen years or so, with no reported fatalities so far.  /img/vbsmilies/smilies/rolleyes.gif
Joined Apr 3, 2010
I would be happy to debate this guy anytime. Th newsletter he mailed you is loaded with bacteria.
      Chopped onions. In most cases after chopping or slicing or dicing they are cooked and subject to heat.
If using diced in raw state, they can be put in a strainer and blanched in boiling water for 30 seconds then cooled . They can also be placed in a clean kitchen towel and run under cold water then squeezed out. This keeps them white and they last longer because you have just removed the oil of onion by doing this. Bacteria is on everything. even the fork given to you  in a restaurant rolled in a napkin has bacteria on it as does the knife. We could go on and on like Howard Hughes did simply keep yourself in an air tight room, wear a mask filter.and don't touch anyone or thing. I call this paranoia. Keep on chopping.
Joined Aug 13, 2006
Actually, I've read that onions actually kill bacteria.  I believe onions have been used to disinfect wounds in emergency situations.  I don;t remember the source, but i remember that it seemed serious, not some new age natural healing with funneling of rays from the stars or anything, but that there were actual antibiotic properties, if mild, in onions.  I don't feel like looking it up but you might want to.

I have actually heard that once an onion is cut it's taste leaves it very fast and you should just toss it.  But that;s another question.  I rarely have any piece of leftover onion anyway, so not a problem.  
Joined Feb 8, 2009
........Nathans Hot dogs, mustard, relish, lots of chopped Bacteria laced onions, Call a Doctor, I'm going in.....................Chef Bill
Joined Feb 4, 2010
Nonsense. I had cut onions stored in a wide-mouth jar in the fridge that I eat raw or use it in cooking. It sits in there sometimes for many days yet I never had problems eating onion. Even though high in sugar, the environment is likely to be hostile to microorganisms except mold.
Joined Aug 4, 2000
Like garlic, onions have a high sulfur content (edit) that bacteria seem to dislike..
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