"We must face the reality that we live in a microbial ocean," said Sam Beattie, PhD, an assistant professor of food science and human nutrition at Iowa State University.
"Microorganisms are literally everywhere, including on and inside of us and most of the food that we eat. Fortunately, most do not make us ill. Bacteria are found in the soil in which the food is grown, in the water that it is irrigated with, in the feces and on the hands of those that harvest and handle it, on animals that pass through and over the fields leave their waste, on pests that eat it or live on it, in containers that hold food during transit to processing, almost everywhere through processing."
Dr. Beattie said it's almost impossible to ensure that there will not be any nasty disease-causing "bugs" on any raw agricultural product, such as spinach and other packaged greens. Lettuce is one vegetable that cannot be cooked to kill the germs, and chemicals cannot be used to kill them either.
He explains more about animal contamination: "Control over the animals that overfly, graze, slither, crawl, and are otherwise naturally present in a field is impossible. An outbreak could come from something as simple as deer excrement on or near the leaves of a plant. The actual feces may be washed off by rain, irrigation, or other means, but the contamination has occurred."
What Can You Do?
- Buy food from reputable stores that have adequate cooling for prepackaged greens. Cooling keeps fresh produce fresh and bacteria from multiplying. Look for code dates on the bag. Buy the freshest you can find.
- Look for obvious signs of deterioration in the product – brown leaves, wilted leaves, overly moist or wet, water accumulation in the bag, swollen bags.
- Once purchased, keep the cut produce cold in your refrigerator. Use it immediately.
- Washing with cold running water will do little to remove more bacteria.
- Eat well-cooked meats and pasteurized juices.
Food processing simply can't eliminate bacteria in fresh foods. "Bacteria are tough to kill," Dr. Beattie said. "During the growing and processing of pre-cut fruits or bagged leafy vegetables, there are several steps that are designed to reduce or eliminate many of the bacteria, but the processing steps must be mild enough to avoid destruction of the produce."
He considers the entire food supply safe, and reports that pre-packaged foods are as safe as most other fresh foods. But it is important to look at how much handling of the fresh food occurs.
The most common "bugs" in food are:
Campylobacter – a bacteria that causes fever, diarrhea, and abdominal cramps. These bacteria live in the intestines of healthy birds, which is why most raw poultry meat has campylobacter in it. Eating undercooked chicken, or other food that has been contaminated with juices dripping from raw chicken is the most frequent source of this infection.
Salmonella – a bacteria that is widespread in the intestines of birds, reptiles, and mammals. It can spread to humans through a variety of animal foods. It causes salmonellosis, with syptoms of fever, diarrhea, and abdominal cramps. In people with a weakened immune system, it can cause a life-threatening infection.
E. coli O157:H7 – a bacteria found in cattle and similar animals. Humans become sick with E. coli by consuming food or water that has been contaminated with microscopic amounts of cow feces. Symptoms include severe and bloody diarrhea, and painful cramps. More serious complications, such as kidney failure, occur in 3 to 5 percent of cases.
Calcivirus (Norwalk and Norwalk-like virus) – a virus that's passed from one infected person to another. It causes severe nausea, vomiting, diarrhea, and stomach cramps. Infected kitchen workers can contaminate a salad or sandwich as they prepare it, if they have the virus on their hands.
If you think you are infected, see your doctor right away! |
