As every college student knows, pizza never goes bad. After all, you can leave it sitting out all night, eat a slice for breakfast, and head to class, right? Well, the good news is that most of today's college students either have incredibly strong immune systems or are incredibly lucky, because this is not true. Pizza take out has limits as to how long it can set out and still be decent to eat. The meat, cheese, and sauce on a pizza can all grow dangerous bacteria if left at room temperature too long. Here are some guidelines to use with ordered pizza when storing it for a later meal.

Remember, Pizza Is Perishable!

Some foods are considered non-perishable, but pizza is not one of them. If you leave it out too long and then eat it, you can get sick. Pizza has meat and cheese on it, and these can harbor dangerous bacteria, including Staphylococcus, Salmonella, and E. Coli.

Most pizzas contain trace amounts of these bacteria, but these low amounts are not dangerous. As long as the pizza is kept either hot or cold, it is fine to eat. However, when it is left a room temperature for too long, the bacteria begin to grow, soon reaching dangerous levels that can cause severe illness. The dangerous temperatures are 40 to 140 degrees Fahrenheit, which is the range that normal room temperature falls in, so leaving the pizza out makes it dangerous, if not deadly.

Understanding the Two-Hour Rule

According to the U.S. Department of Agriculture (USDA), any food, whether hot or cold, that has been left at room temperature for two hours or longer needs to be thrown out. If the temperature is above 90, such as at an outdoor picnic on a hot day, the food needs to be thrown out after just one hour. The best temperature for hot foods is any temperature that is over 140 degrees. Cold foods need to be kept at a temperature of 40 degrees or less.

Keep in mind that your pizza may not arrive at the right temperature. If you transported the pizza yourself or the delivery driver had a long route to take, the temperature could have dropped below 140 degrees before you even started eating it. Use a food thermometer to determine the temperature of the pizza. If it is below 140 degrees, do not leave it out for the two-hour maximum. It has already cooled below the ideal temperature, allowing the harmful bacteria to grow.

Storage Tips for Pizza

If you know that you will need to have the pizza available for longer than two hours, use your oven to keep it above 140 degrees. Put the oven's temperature setting on "keep warm" or a similar choice, and leave the pizza in its cardboard box in the oven. The pizza box will not burn at this temperature, but you will be able to keep the pizza safe.

When you are done with the pizza, store it in a sealed container in the refrigerator. Many people like to store the pizza in its cardboard box. While this is fine health-wise, it can cause the pizza to dry out faster. You can also freeze the pizza. Pizza stored in the refrigerator is typically good for three or four days. You can keep it in the freezer for up to two months.

So the next time you are at a party and are reaching for that now-cold piece of pizza, remember that it is a prime place for dangerous bacteria to grow. If you are the host of the party, keep your guests safe by putting the pizza away after two hours. Remember, you may have eaten left-out pizza in the past, but every time you do, you are playing with fire. Protect yourself by handling your take out safely every time!