Handle Leftovers with Care
Being a busy mom I rely heavily on two things: leftovers and the microwave. How else would I heat up a quick lunch at work as I rush to get back to a conference call? How would I re-heat the dinner my husband missed due to our mismatched schedules?
Still, despite feeling crunched for time, I do take care to treat my food in a way that protects my family from foodborne illness. There’s much more to the safe handling of leftovers than most people realize, and following a few simple tips can save you—and your loved ones—from illness.
Put leftovers in shallow containers to cool quickly
The center of that big pot of chili you stick in the fridge isn’t going to cool down within 2 hours, and that warm spot in the middle can allow bacteria to grow. The smaller the portion size, the faster it will cool in the refrigerator. And when you go to heat it up in the microwave, it will heat much more quickly and evenly too. [USDA recommends packing leftovers so that they are less than 2 inches deep.]
Refrigerate within 2 hours
Bacteria grow rapidly at warm temperatures, and after just a few hours can reach levels that can cause illness. Refrigeration slows the growth of bacteria. The recommended temperature for your fridge is 40 °F or below (use an appliance thermometer to see how cold it is).
Foods should be refrigerated within 2 hours of preparation. Even though it may seem energy efficient to let foods cool down on the counter before sticking them in the fridge, there can be a risk if they are left out too long.
It’s important to remember that the clock starts ticking the moment your food is done cooking—so when dining out, consider the time the food is at the restaurant and the time you travel home. For more details, see Safe Handling of Take-Out Foods.
Reheat thoroughly
The microwave is just another way to heat food. The microwaves bounce around and literally “excite” the food. However, the microwaves may not hit every part of the food evenly. In foods with multiple ingredients (like a casserole) some ingredients may get more “heated” than others.
It’s really important that all parts of reheated food reach 165 °F before they are eaten. There are a few ways to ensure this happens:
- Stir the food in the middle of heating;
- Let the food sit for a few minutes after it finishes in the microwave to ensure the food cooks evenly. During this “standing time,” the cold parts of the food will absorb some heat from the hotter portions. Many microwave meals recommend this, so pay attention to microwave instructions.
- After the “standing time,” check the food with a food thermometer.
For more info on reheating in a microwave, see the video How to Properly Cook Foods in the Microwave.
Drinking Raw Milk: More Details on the Risks
In response to my recent blog, Drinking Raw Milk: It’s Not Worth the Risk, we received a number of questions. Here are some of the most frequently asked questions from our readers, along with my answers.
Why focus on raw milk? What about other foods that have made people sick?
We get a lot of questions from people who are trying to decide whether or not to drink raw milk, and we want to provide them with science-based information on the risks of drinking raw milk.
I work with the group at the Centers for Disease Control and Prevention (CDC) that investigates outbreaks of foodborne illnesses caused by germs like Salmonella and E. coli O157:H7 (a dangerous form of E. coli). Over the years, we have collected extensive data based on experience investigating these outbreaks. Many different foods have been associated with recent outbreaks, such as unpasteurized juice and cider, eggs, and sprouts.
When determining if one food is riskier than another, it is important to understand how many people consume that food. For example, did you know that an estimated 4 percent of dairy products consumed in the United States are unpasteurized, based on a 2006-2007 FoodNet Population Survey, yet more than half of dairy-associated outbreaks are linked to raw milk products?
I know people who have been drinking raw milk for years, and it’s never made them sick. Why is that?
Several things can affect whether or not a person becomes sick after consuming a contaminated food or drink. These include the number and type of germs contaminating the food or drink, as well as the immune defenses of the person who consumes the food or drink.
The presence of germs in raw milk is unpredictable. The number of disease-causing germs in the raw milk may be too low to make a person sick at first, but the germs may later multiply so that there are enough to make the same person seriously ill. As seen in these videos, for some people, drinking contaminated raw milk just once could make them really sick; for others, illness comes after years of drinking raw milk.
I’ve heard that raw milk has enzymes that kill dangerous bacteria. Is that true?
No, the enzymes in raw milk are not strong enough to kill dangerous bacteria. In the United States, pasteurization is the only method routinely used to eliminate disease-causing organisms in milk.
My farmer has set up humane and sanitary conditions for raising his animals and producing raw milk. His animals are really healthy. Doesn’t this ensure that his milk is safe?
Even animals that appear healthy and clean may carry germs that can contaminate milk. Adhering to good hygienic practices during milking can reduce the risk of contaminating the milk, but it doesn’t eliminate it. If the milk is raw, small numbers of bacteria might multiply and grow in the milk before someone drinks it. No matter what precautions the farmer takes, it’s impossible to guarantee that raw milk is free of harmful germs.
What about raw milk that’s been laboratory tested for bacteria?
Negative tests do not guarantee that raw milk is safe to drink. People have become very sick from drinking raw milk that came from farms that regularly tested their milk for bacteria, and whose owners were sure that their milk was safe.
What are the statistics on outbreaks of illness related to raw milk?
Among dairy product-associated outbreaks reported to CDC between 1973 and 2009 in which the investigators reported whether the product was pasteurized or raw, 82% were due to raw milk or cheese. From 1998 through 2009, 93 outbreaks due to consumption of raw milk or raw milk products were reported to CDC. These resulted in 1,837 illnesses, 195 hospitalizations, and 2 deaths. Most of these illnesses were caused by Escherichia coli O157, Campylobacter, or Salmonella. It is important to note that a substantial proportion of the raw milk-associated disease burden falls on children; among the 93 raw dairy product outbreaks from 1998 to 2009, 79% involved at least one person less than 20 years old.
Reported outbreaks represent the tip of the iceberg. For every outbreak and every illness reported, many others occur, and most illnesses are not part of recognized outbreaks.
Keep in mind that reported outbreaks represent the tip of the iceberg. For every outbreak and every illness reported, many others occur, and most illnesses are not part of recognized outbreaks.
Can outbreaks be caused by pasteurized milk products?
Pasteurized milk and cheese products can cause outbreaks, but these are usually due to contamination that occurs after the pasteurization process. Also, the most common germ that affects pasteurized milk products is norovirus, which is typically spread from one person to another, not from animals to people. This is different from the germs that can most often contaminate raw milk like Salmonella and E. coli O157 H7, which are spread from animals to people. Also illness from norovirus typically lasts for only 2 days, whereas illness from Salmonella and E. coli is usually more serious.
For more statistics and other information, see Raw Milk Questions and Answers.
Updated on: November 18, 2011
Drinking Raw Milk: It's Not Worth the Risk
There are many reasons why some people are thinking about drinking raw milk these days. (Raw milk is milk that has not been pasteurized to kill harmful germs.) Some people want to eat less processed food. Others have heard that raw milk contains more of certain nutrients than pasteurized milk, or that it can prevent or even solve various health problems. Still others think of buying raw milk as one way to support local farmers and sustainable agriculture.
As a public health epidemiologist and veterinarian, I know firsthand how animals and their germs can contaminate all kinds of food, including milk. Also, in my job in the Outbreak Response and Prevention Branch at CDC, I help investigate outbreaks caused by contaminated food and contact with infected animals.
If you’re thinking about adding raw milk to your diet (or your family’s diet), it’s important for you to understand the risks of drinking raw milk.
Why raw milk is dangerous
Raw milk can carry harmful bacteria and other germs that can make you very sick or kill you. Yes, it’s true that it’s possible to get “food poisoning” or foodborne illnesses from many foods, but raw milk is one of the riskiest of all. Raw milk and products made from raw milk (such as cheeses and yogurts) can cause serious infections, such as Salmonella, Listeria, and E. coli.
What happens if you get sick from raw milk
Getting sick from raw milk can mean many days of diarrhea, stomach cramping, and vomiting. Less commonly, it can mean kidney failure, paralysis, chronic disorders, and even death. The seriousness of the illness is determined by many factors, such as the type of germ, the amount of contamination, and the person’s immune defenses.
Speaking of immune defenses… it’s important to remember that some people are at higher risk of getting sick from drinking raw milk. The risk is greater for certain age groups, such as infants, young children, and older adults. It’s also particularly risky for pregnant women (and their unborn babies) and those with weakened immune systems, such as people with cancer, an organ transplant, or HIV/AIDS.
Though some people are at higher risk of getting sick from raw milk, even healthy adults and older children can get seriously ill. Those who recover often suffer from life-long medical consequences. To see how devastating these illnesses can be, check out these real-life stories about the dangers of raw milk.
Even healthy animals may carry germs that contaminate raw milk
Outbreaks of illness related to raw milk have been traced back to both grass-fed and grain-fed animals. Raw milk supplied by “certified,” “organic,” or “local dairies has no guarantee of being safe.
How to stay safe
To keep your family safe, follow these simple tips:
- Always drink pasteurized milk. Check the label or package to be sure.
- If you prefer organic milk, make sure that it’s pasteurized. Raw, organic milk is not safe.
- If you or a member of your family consumes raw milk and then becomes ill, call your health care provider immediately. If it’s an emergency, call 911.
For more information, including questions and answers about raw milk, see Food Safety and Raw Milk (CDC).