Hold The Onions

A friend sent an interesting email the other day and I wanted to post it here and expand on my personal experience. So many sensational email warnings are circulating these days that Snopes can't research the facts fast enough. This one is quite true however, even if it may be remote.

The author writes:

"I have used an onion which has been left in the fridge, and sometimes I don't use a whole one at one time, so save the other half for later.

Now with this info, I have changed my mind....will buy smaller onions in the future.

I had the wonderful privilege of touring Mullins Food Products, Makers of mayonnaise. Mullins is huge, and is owned by 11 brothers and sisters in the Mullins family. My friend, Jeanne, is the CEO.

Questions about food poisoning came up, and I wanted to share what I learned from a chemist.

The guy who gave us our tour is named Ed. He's one of the brothers. Ed is a chemistry expert and is involved in developing most of the sauce formulas. He's even developed sauce formula for McDonald's.

Keep in mind that Ed is a food chemistry whiz. During the tour, someone asked if we really needed to worry about mayonnaise. People are always worried that mayonnaise will spoil. Ed's answer will surprise you. Ed said that all commercially made mayo is completely safe.

"It doesn't even have to be refrigerated. No harm in refrigerating it, but it's not really necessary." He explained that the pH in mayonnaise is set at a point that bacteria could not survive in that environment. He then talked about the quaint essential picnic, with the bowl of potato salad sitting on the table and how everyone blames the mayonnaise when someone gets sick.

Ed says that when food poisoning is reported, the first thing the officials look for is when the 'victim' last ate ONIONS and where those onions came from (in the potato salad?). Ed says it's not the mayonnaise (as long as it's not homemade mayo) that spoils in the outdoors. It's probably the onions, and if not the onions, it's the POTATOES.

He explained, onions are a huge magnet for bacteria, especially uncooked onions. You should never plan to keep a portion of a sliced onion.. He says it's not even safe if you put it in a zip-lock bag and put it in 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 (and doubly watch out for those onions you put in your hotdogs at the baseball park!)

Ed says if you take the leftover onion and cook it like crazy you'll probably be okay, but if you slice that leftover onion and put on your sandwich, you're asking for trouble. Both the onions and the moist potato in a potato salad, will attract and grow bacteria faster than any commercial mayonnaise will even begin to break down.

So, how's that for news? Take it for what you will. I (the author) am going to be very careful about my onions from now on. For some reason, I see a lot of credibility coming from a chemist and a company that produces millions of pounds of mayonnaise every year.

Also, dogs should never eat onions. Their stomachs cannot metabolize onions. Please remember it is dangerous to cut onions and try to use it to cook the next day, it becomes highly poisonous for even a single night and creates toxic bacteria which may cause adverse stomach infections because of excess bile secretions and even food poisoning."

As a chef of over 25 years I can attest that commercially made mayonnaise is a benchmark product and is pretty much bulletproof. Cooked potatoes however are highly susceptible to promoting foodborne illness. They are a perfect medium for bacterial growth.

Peeled and/or chopped raw garlic that is stored in an oxygen-void atmosphere (ie- canned or vacuum sealed, or in oil) can harbor the bacteria that causes botulism. I was always taught that but I can't prove it. Has to do with sulfur compounds.

Onions I'm not so sure about. In all my years I can remember twice hearing about onions promoting salmonella (from unreliable sources). I don't remember it from several rounds of sanitation certification, but I don't remember a lot of things. I do know that most foods spoil at some some point and eating spoiled food isn't cool.

We are aware in the foodservice industry that what causes foodborne illness is seldom the most obvious suspect. The biggest culprit is cross-contamination (poor food handling practices) and the greatest safeguard is proper hand washing.

Over my career of 27 years in the biz I am aware (not that there haven't been more) of only one time that someone legitimately got sick eating food from one of my kitchens. One day in 2006 something like 5 staff members of a hospital I worked at in southern California got sick eating tuna salad that was made that day. No explanation ever made sense and we never figured out what caused it.

First of all let's look at what it takes to create foodborne illness. Whole books are written on this topic but I will discuss the most commonly known and feared "food poisoning" scenarios. The ones that most people talk about are Salmonella, Botulism, and E.Coli. These illnesses are caused principally by bacteria, and either by ingesting the actual bacteria or the toxins that the associated bacteria produce (in which case you're probably ingesting the bacteria as well).

Bacteria are living creatures, and like most living creatures they require certain conditions to survive and multiply. We live, sleep, eat, drink, and breathe potentially harmful bacteria all of the time, and our immune systems adapt to their presence. Normally we are perfectly healthy and filled with little critters that we don't know are there.

It's when they are allowed to multiply that they cause problems. To do that they require time (could be hours, could be days), temperature (between 41 and 135 deg. F), food (usually sugar/starch, and protein), moisture, oxygen (though some prefer the absence of oxygen), and the right pH (typically neutral, between 6 and 8 on the pH scale).

Mayonnaise is made from oil, eggs, and vinegar. Due to the addition of lemon juice and/or vinegar commercial mayonnaise has an acidic pH level of 3.8 to 4.6. Bacteria cannot live below 4.5. Interestingly, if you try to make mayonnaise without the acid, you will not get mayonnaise. The acid is required to achieve emulsion. Because of the shelf-life extending qualities of commercial mayonnaise it is often used in the kitchen as a base for other cold sauces and dressings.

Potatoes on the other hand offer the perfect moisture content, food availability, and neutral pH to make critters feel right at home. Even if the surface is coated with caustic mayonnaise the potato itself dilutes the acid content and those little suckers bore inside and set up shop. Leave it on the picnic table for a couple hours and it's on.

Professionally, local and federal health codes dictate that if a prepared food product is allowed to sit in the "danger zone" of 41-135 deg F. for more than 4 hours it must be discarded. Good policy to follow at home as well. So why did the chicken legs that mom always left on the counter overnight never make us sick when we ate them two days later? Who knows.

Basically, buy good quality ingredients from reputable sources, store and prepare them properly, wash your hands, and enjoy your life and your food! We'll all die from food poisoning if something else doesn't kill us first.

By the way, an interesting little tidbit I picked up as a beekeeper a few years back--honey (in its natural and undiluted state) is the only food that cannot and will not spoil. Bees rock! I could argue that there are a few other unspoilable foods (just made another word), but that's another article altogether.

Follow up:

After writing this article I actually stumbled across a Snopes article about the email I received. Funny. An interesting read that concurs with what I have written.