It's peak summer and millions of Americans are feeling the heat. As temperatures continue to rise, many people are cooling off at the beach.
No beach day is complete without a spread — and all that swimming and playing in the sand can really work up an appetite. However, not all snacks are considered beach-safe, according to experts. The hot summer temperatures and sunshine can easily spoil certain foods, making them a risky or even unsafe option to eat.
"You want to be careful, and the last thing you want is for people to go home and remember the beach trip because they got sick," Dr. John Torres, NBC News senior medical correspondent, told TODAY in a segment aired July 7.
When food sits out at unsafe temperatures for too long, disease-causing bacteria can grow to dangerous levels, per the U.S. Department of Agriculture. These include pathogens like salmonella, E. coli, campylobacter, clostridium perfringens and staphylococcus aureus — which can cause diarrhea and vomiting, TODAY.com previously reported.
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Bacteria multiply most rapidly in "the danger zone," or between 40 degrees and 140 degrees Fahrenheit, says Torres. Perishable foods should never sit out of refrigeration for more than two hours, per the U.S. Department of Agriculture.
If the surrounding temperature is higher than 90 degrees — which is common for beach weather — food should be left out for no longer than one hour, TODAY.com previously reported.
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In any case, you should aim to keep food refrigerated until you eat it, Torres notes. Using a high-quality portable cooler can help keep your food cool while you enjoy the beach, but it can be hard to control the temperature and keep it below 40 degrees Fahrenheit all day long. According to Torres, you should avoid bringing these foods on your next beach day in order to stay safe.
Cold cuts that require refrigeration
They're portable, packable and a beach favorite. But before you pack up a bunch of sandwiches or subs, consider what will go inside and how you'll store them at the beach.
If the sandwiches are made with deli meats or cold cuts — such as sliced turkey, ham, chicken, roast beef, salami, bacon or bologna — these need to be refrigerated until they are ready to eat, says Torres.
Although deli meats are often cured and processed to help prevent spoilage and contamination, they can still contain disease-causing bacteria that makes you sick, TODAY.com previously reported. When left sitting out in the danger zone, these bacteria can multiply rapidly.
If you have no way to keep your deli meat sandwiches refrigerated while you enjoy the sand and waves, your safest bet is to skip them or opt for ingredients that don't require refrigeration.
Once you take any deli meat sandwiches out of the fridge or cooler, they should be eaten as soon as possible.
Fresh salads
Fresh salads packed with raw produce like leafy greens may not be your best bet for a beach day, says Torres. Not only can your salad become wilted and soggy in the heat, but any bacteria present can multiply rapidly in warm temperatures.
All raw fruits and vegetables have the potential to contain disease-causing pathogens such as salmonella, e.coli and listeria, and the CDC estimates that these germs on produce cause a large percentage of foodborne illness in the U.S. That's why it’s so important to wash fresh produce before eating, TODAY.com previously reported.
However, washing only reduces the amount of bacteria on the fresh produce, per the CDC. Bacteria love to grow in warm, moist environments — so a big salad in an airtight container sitting out in hot beach temperatures can quickly become the perfect environment for pathogens to thrive.
Anything mayo-based
“Mayo-based potato salad is always one of those big things that cause a lot of issues,” says Torres. Although it's bought from a non-refrigerated shelf, mayonnaise does need to be refrigerated, and any salad or dish containing mayonnaise can only be left out at temperatures above 40 degrees Fahrenheit for two hours before it should be discarded, according to the USDA.
However, it's not just the mayonnaise in these foods that can spoil and grow bacteria. According to the USDA, commercial mayonnaise actually contains an acid (vinegar or lemon juice), which helps prevent bacterial growth.
However, mayo-based salads or dressings are often made in large batches and left to sit at room temperatures while they are served buffet-style. If left at an unsafe temperature for too long, this also allows the food mixed in — potatoes, boiled eggs, meat, poultry or fish — to become a medium for bacteria to grow, per the USDA.
Mayo-based foods need to be refrigerated until they are served for eating, says Torres. So it's probably wise to avoid bringing these dishes to the beach entirely and enjoy them at home instead.
Uncooked meats
Grilling is a favorite beach activity for many. But bringing a bunch of raw hamburger meat or chicken that will sit around at various temperatures before it is barbecued is not the best idea. In general, Torres recommends against bringing raw or uncooked meats to the beach ever.
Raw meat can harbor pathogens such as E. coli, yersinia, staphylococcus aureus, clostridium perfringens and campylobacter— which can cause mild to severe gastrointestinal illness, TODAY.com previously reported.
If you decide to bring raw meat, make sure it's stored properly in a cooler below 40 degrees Fahrenheit until it's ready to be cooked, and keep it sealed and separate from any other foods that won't get cooked in the cooler.
According to USDA guidelines, beef should be cooked to a minimum internal temperature of 145 degrees Fahrenheit, poultry to 165 degrees Fahrenheit and fish to 145 degrees Fahrenheit.
Precut fruits
Precut fruit is notorious for containing foodborne pathogens, such as salmonella. These include include papayas, peaches and a major culprit, melon — including honeydew, cantaloupe and an all-time beach favorite, watermelon.
When the melons are cut, this can transfer bacteria on the surface of the fruit into the flesh, TODAY.com previously reported. There have been numerous outbreaks of salmonella linked to precut melons in recent years. Any bacteria that could be transferred from hands, knives or surfaces, like cutting boards, can end up on the sliced fruit where it can grow and multiply, especially in the hot beach weather.
Sliced fruit can also get warm faster and draw insects, says Torres. Instead of buying presliced fruit for your next beach trip, Torres recommends bringing the whole fruit and cutting it up at the beach instead — just make sure you have clean hands and use a clean knife and cutting board.
This story first appeared on TODAY.com. More from TODAY: